FLUORIDE ACTION NETWORK PESTICIDE PROJECT

Return to FAN's Pesticide Homepage

Return to Abstracts Page


1985 Fluoride Abstracts. Part 1.

Abstracts for the following years:
Part 1 - mainly biochemistry and physiology (brain, hormonal, G-proteins, etc.)
Part 2 ("b") - all other

2007

2007-b

2004

2004-b

2001

2001-b

1998

1998-b

1995

1995-b

1992

1992-b

1989

1989-b

1986

1986-b

1983

1982

1976 -
1977
1970 -
1971

2006

2006-b

2003

2003-b

2000

2000-b

1997

1997-b

1994

1994-b

1991

1991-b

1988

1988-b

1985

1985-b

1981

1980

1974 -
1975
1968 -
1969

2005

2005-b

2005-b continued

2002

2002-b

1999

1999-b

1996

1996-b

1993

1993-b

1990

1990 -b

1987

1987-b

1984

1984-b

1979

1978

1972 -
1973
Up to
1967

Polar Biol 1985 5:31-34.

The distribution of fluoride in some Antartic seals.

Adelung D, Bossmann K, Rossler D.

As cited in: Canadian Water Quality Guidelines for the Protection of Aquatic Life: Inorganic Fluorides. Environment Canada, August 2001.

Adelung et al. (1985) examined tissue levels of three different Antartic seals, the crabeater seal (Lobodon carcinophagus), the Weddell seal (Leptochynotes weddelli) and the Fur seal (Arctocephaus tropicalis) which feed on krill. The tissue levels of inorganic fluorides in these three seal species were similar [to] those in non-krill-eating marine or terrestrial invertebrates. The soft tissue inorganic fluoride levels ranged from 2.3 to 9.1 mg F/g dw, with the lowest amounts found in adipose tissue, and the highest amounts in the brain. Levels in the blood were also low (0.006 mg F/g)... (page 33)


Fluoride 1985; 18(2):71

Editorial

New light on the mechanism by which fluoride interferes with enzyme action

(Abtracted from New Scientist Feb 28, 1985: 105:20)

Three American scientists using x-ray analysis of fluoridated enzymes have disclosed, according to the New Scientist, that "fluoride switches off the enzyme by attacking its weakest links - the delicately-balanced network of hydrogen bonds surrounding the enzyme's active site."

It has been known for many years, the article states, that fluoride inhibits enzymes, thus preventing these natural catalysts from carrying out their essential tasks. The crystal structure of a fluoride-inhibited peroxidase enzyme shows that the fluoride ion attaches itself to the iron atom at the heart of the enzyme and then disrupts the active site of attracting groups that can form strong hydrogen bonds to itself. Ultimately, this inactivates the enzyme by changing its shape, or molecular conformation.

Hydrogen bonds are weak interactions between the hydrogen atoms in O-H and N-H chemical bonds, and a second oxygen, nitrogen or fluoride atom. The fluoride ion is particularly good at forming such bonds because of its small size and negative charge. Hydrogen bonds are weaker than normal chemical bonds. Many of them, however, can hold complex systems together in very specific patterns.

Steven Edwards, Thomas Poulos and Joseph Kraut, of the Department of Chemistry at the University of California in San Diego [1], prepared a crystal of the fluoride form of cytochrome C peroxidase and looked at it using x-ray crystallography. The structure of the fluorided enzyme was compared with that of the ordinary enzyme, so that changes in the active site could be monitored. These changes although small are highly significant.

The free enzyme has a delicate network of hydrogen bonds that is based on water molecules around the active heme site. One water molecule is directly bonded to the iron atom. This water is hydrogen bonded to a particular histidine group labled His-52 and to a second water molecule which in turn is hydrogen bonded to a nearby arginine group (ARG-48). This fine molecular web awaits a peroxide molecule which it captures and converts to water.

In the fluoride-inhibited enzyme, the ARG-48 has moved far away from the surface and much closer to the heme site. It is attracted by the presence of the fluoride, which is directly bonded to the iron atom, and which is capable of forming much stronger hydrogen bonds than the water molecule it has displaced (200 pm closer in the case of ARG-48 - quite a big jump in molecular terms). His-52 has also moved closer to the active site; this repositioning of ARG-48 now prevents it from doing its job - the fluorde blocks the enzymes.

The article concludes that many enzymes are inhibited by fluoride even when it is present only in parts per million levels.

[1] Edwards SL, Poulos TL, Kraut J (1984).The crystal structure of fluoride-inhibited cytochrome c peroxidase. J Biol Chem Nov 10;259(21):12984-8.



http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=4039451&dopt=Abstract

Pharmacol Biochem Behav 1985 Mar;22(3):479-82

Comparative behavioral effects of CNS cholinesterase inhibitors.

Moss DE, Rodriguez LA, McMaster SB.

Phenylmethanesulfonyl fluoride, methanesulfonyl fluoride, and physostigmine were compared on the efficacy with which each could suppress methylphenidate-induced stereotyped gnawing, an extrapyramidal motor behavior. Whereas physostigmine produced powerful suppression of the stereotypy, the sulfonyl fluorides did not produce any clear behavioral effect. Biochemical experiments conducted with the behavioral tests demonstrated that the sulfonyl fluorides produced inhibition of whole brain, caudate, cortex, cerebellum, hippocampus and brain stem cholinesterate equal to that produced by physostigmine. The reason for the marked discrepancy between the behavioral effect of physostigmine and the sulfonyl fluorides is unknown. It is, however, clear that the effect of the various drugs on extrapyramidal motor behaviors is not a simple function of the degree to which each inhibited CNS cholinesterase.

PMID: 4039451 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3917489&dopt=Abstract

J Neurochem 1985 Feb;44(2):370-5

Alkenylhydrolase: a microsomal enzyme activity in rat brain.

Gunawan J, Debuch H.

Rat brain microsomes have the capacity to liberate radioactive free aldehydes from 1-[1-14C]alk-1'-enyl-sn-glycero-3-phosphoethanolamine (lysoplasmalogen). Glycerophosphoethanolamine was found using 1-alk-1'-enyl-sn-glycero-3-phospho-[3H]ethanolamine. The ratio of both products released by lysoplasmalogenase action was 1:1. Another enzymic activity could be demonstrated, which hydrolyzes lysoplasmalogen at the hydrophilic part of the molecule, a lysophospholipid phosphodiesterase. Thus, 1-[1-14C]alk-1'-enylglycerol was detected as well as [3H]ethanolamine, again in a molar ratio, from the respective labeled substrates. This enzyme possesses nearly the same affinity toward the substrate as lysoplasmalogenase. Whereas the lysophospholipid phosphodiesterase is totally inhibited in the presence of NaF or EDTA, lysoplasmalogenase activity is not affected by these reagents. 1-[1-14C]Alk-1'-enylglycerol acts also as substrate for lysoplasmalogenase, which liberates radioactive aldehydes at the same rate as from lysoplasmalogen. Because the apparent Km and Vmax values are nearly identical for both substrates, the enzyme activities are inhibited in the same way, and the pH optimum is about 7.2 in both cases, it is concluded that both substrates were attacked by the same enzyme. The enzyme does not differentiate between a substrate substituted at the sn-3 position of glycerol and one that is not. It requires only a free OH group at the sn-2 position. Phosphoethanolamine phosphatase activity was also determined under our experimental conditions.

PMID: 3917489 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3931554&dopt=Abstract

Arch Biochem Biophys 1985 Oct;242(1):137-45

Calmodulin-dependent protein kinases purified from rat brain and rabbit liver.

Schworer CM, McClure RW, Soderling TR.

A calmodulin-dependent protein kinase was purified from rat brain by the same protocol used previously for a rabbit liver calmodulin-dependent glycogen synthase kinase. The rat brain kinase readily phosphorylated rabbit skeletal muscle glycogen synthase at sites 1b and 2, the same sites phosphorylated by rabbit liver calmodulin-dependent kinase. The two kinases have other similarities: substrate specificity, potent inhibition by sodium fluoride, and nearly equal Ka's (10-20 nM) for calmodulin. Also, both enzymes have similar Stokes radii, 70 A (rabbit liver) and 75 A (rat brain), but quite different sedimentation coefficients, 10.6 S and 17.4 S, respectively. Consequently, the calculated molecular weights are also different: 560,000 for the brain enzyme and 300,000 for the liver enzyme. The major subunit of the rat brain kinase appears to be a single 51-kDa peptide, not a doublet pattern of 51- and 53-kDa subunits that is characteristic of the rabbit liver enzyme. Our findings are consistent with the hypothesis that the rat brain and rabbit liver enzymes belong to a class of closely related calmodulin-dependent protein kinases, possibly isozymes. This class of enzymes may be responsible for regulating several of the known calcium-dependent physiological functions.

PMID: 3931554 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=4026795&dopt=Abstract

Biochem J 1985 Jun 15;228(3):537-44

Characterization of [3H]di-isopropyl phosphorofluoridate-binding proteins in hen brain. Rates of phosphorylation and sensitivity to neurotoxic and non-neurotoxic organophosphorus compounds.

Carrington CD, Abou-Donia MB.

The experiments described in this paper were designed to isolate [3H]di-isopropyl phosphorofluoridate-binding proteins by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis for the purpose of characterizing and identifying potential initiation sites for organophosphorus-compound-induced delayed neurotoxicity. The major Paraoxon-insensitive Mipafox-sensitive binding protein (Mr 160 000) was found to be identical with one previously identified as neurotoxic esterase, an enzyme that has been proposed to be the target site for organophosphorus-compound-induced delayed neurotoxicity. However, two other binding proteins with suitable binding characteristics were also found in smaller amounts, one of which has not been detected previously. Di-isopropyl phosphorofluoridate was found to phosphorylate all three of these proteins at rates similar to the rate at which neurotoxic esterase is inhibited by di-isopropyl phosphorofluoridate. Varying the concentration of di-isopropyl phosphorofluoridate or the time of incubation produced similar increases in binding to each of the labelled proteins. This suggests that the reaction rates of di-isopropyl phosphorofluoridate with proteins may be described by first-order kinetics, and the concentration of the Michael is complex formed during binding is minimal for all the phosphorylated proteins. The recovery of the binding activity in the 160 000-Mr band was found to be similar to the recovery of neurotoxic esterase activity, lending further support to the contention that this band is identical with neurotoxic esterase.

PMID: 4026795 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2859406&dopt=Abstract

Methods Find Exp Clin Pharmacol 1985 Feb;7(2):79-81

Striatal neurochemical changes and motor dysfunction in mipafox-treated animals.

Matin MA, Hussain K.

5 mg/kg mipafox [N,N'-bis(1-methylethyl)phosphordiamidic fluoride] was administered s.c. daily for 60 days in rats. The animals developed motor dysfunction-muscle twitchings, fasciculations and slight ataxia towards the end of the experimental period; the motor dysfunction was accompanied by neurochemical changes in the corpus striatum which included significantly reduced levels of cholinesterase, neurotoxicesterase, dopamine and GABA. The neurochemical imbalance in the corpus striatum may be related to motor dysfunction in mipafox-treated animals.

PMID: 2859406 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3836685&dopt=Abstract

Alcohol Drug Res 1985-86;6(6):379-86

Differential effects of cytosolic modulators of fluoride-stimulated adenylate cyclase activity in striatum and cerebral cortex.

Rabin RA, Bode DC, Molinoff PB.

The effects of sodium fluoride (NaF) and ethanol on adenylate cyclase activity were investigated in mouse and rat striatum and cerebral cortex. In a crude homogenate of striatum, NaF (10 mM) had no effect on adenylate cyclase activity even though guanyl-5'-yl-imidodiphosphate (GppNHp) increased enzyme activity by two-fold. Addition of 300 mM ethanol increased basal and GppNHp-stimulated activity and allowed expression of an effect of NaF. Stimulation of adenylate cyclase activity by NaF was also observed after sedimentation and resuspension of membranes. Readdition of the supernatant to washed membranes caused a decrease in maximal NaF-stimulated activity without any change in the concentration of NaF required for half-maximal stimulation. The inhibitory effect of the supernatant was resistant to heat but was eliminated by the addition of ethanol or perchloric acid. Inhibition of NaF-stimulated adenylate cyclase activity in striatal tissue was also observed when assays were carried out in the presence of a 20,000 X g supernatant prepared from cerebral cortex. NaF-stimulated activity in cortical tissue was, on the other hand, enhanced in the presence of a 20,000 X g supernatant prepared from either cortex or striatum. This suggests that there is a basic difference between the adenylate cyclase systems of these tissues.

PMID: 3836685 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3930955&dopt=Abstract

Mutat Res 1985 Oct;144(2):89-92

The effect of fluoride on chromosome aberration and sister-chromatid exchange frequencies in cultured human lymphocytes.

Thomson EJ, Kilanowski FM, Perry PE.

Sodium fluoride, at concentrations of up to 60 times the level normally used in drinking water for the prevention of dental decay, was compared with 2 other inorganic salts for its ability to induce chromosome aberrations and sister-chromatid exchanges (SCE) in cultured human lymphocytes. No significant increases in the frequencies of aberrations of SCEs were found.

PMID: 3930955 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=4088985&dopt=Abstract
Probl Endokrinol (Mosk) 1985 Nov-Dec;31(6):25-9
 
[Action of the body fluorine of healthy persons and thyroidopathy patients on the function of hypophyseal-thyroid the system]
 
[Article in Russian]
 
Bachinskii PP, Gutsalenko OA, Naryzhniuk ND, Sidora VD, Shliakhta AI.
 
Altogether 123 persons were examined: 47 healthy persons, 43 patients with thyroid hyperfunction and 33 with thyroid hypofunction. It was established that prolonged consumption of drinking water with a raised fluorine content (122 +/- 5 mumol/l with the normal value of 52 +/- 5 mumol/l) by healthy persons caused tension of function of the pituitary-thyroid system that was expressed in TSH elevated production, a decrease in the T3 concentration and more intense absorption of radioactive iodine by the thyroid as compared to healthy persons who consumed drinking water with the normal fluorine concentration. The results led to a conclusion that excess of fluorine in drinking water was a risk factor of more rapid development of thyroid pathology. Indicators of the fluorine content in daily urine provide most of the information on changes of the fluorine amount in the body.
 
PMID: 4088985 [PubMed - indexed for MEDLINE]

Fluoride 1985; 18(2):111-117

Hyperplastic nodules of thyroid parafollicular cells (C cells) in rats induced by prolonged low dose ingestion of NaF

Okayasu I, Tsuchida M, Yanagisawa F

Department of Pathology, School of Medicine and Department of Epidemiology and Environmental Medicine, Medical Research Institute, Tokyo Medical and Dental University, Tokyo, Japan

Summary: In rats which received drinking water containing 0, 3, 6, 12, 25 ppm NaF (F-) for 20 months, hyperplastic nodules, consisting of thyroid parafollicular cells (C cells) appeared in all F- groups, particularly in those which received 12 and 25 ppm. By immuno-histochemistry and electron microscopy, both calcitonin and characteristic secretary granules were detected in the cytoplasm of these hyperplastic cells. This morphological result was substantiated by the striking increase in the serum value of calcitonin, seen simulataneously in rats with hyperplasia of parafollicular cells. Furthermore, whereas the thyroid follicles were larger in size in the F-groups than in controls, the differences were not markedly significant.

[Note from FAN:
Definition of calcitonin - a peptide hormone, of which eight forms are known; produced by the parathyroid, thyroid, and thymus glands; its action is opposite to that of parathyroid horone in that calcitonin increases deposition of calcium and phosphate in bone and lowers the level of calcium in the blood.
Ref: Stedman's Concise Medical Dictionary for the Health Professions. Illustrated 4th Edition. Ed. JH Dirckx. 2001. Lippincott Williams & Wilkins.]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=4067838&dopt=Abstract
 
J Environ Pathol Toxicol Oncol 1985 Sep-Oct;6(1):9-13
 
Aluminum-fluoride complexes: preclinical studies.
 
Shore D, Sprague SM, Mayor GH, Moreno EC, Apostoles PS, Wyatt RJ.
 
PMID: 4067838 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=4024597&dopt=Abstract

Vrach Delo 1985 Jun;(6):92-5

[Blood serotonin levels and urinary excretion of tryptamine in toxic hepatitis caused by fluoride compounds]

[Article in Russian]

Medvedeva VN.

PMID: 4024597 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=4084631&dopt=Abstract

Biol Reprod 1985 Nov;33(4):854-8

Reversal of the endocrine toxicity of commercially produced perfluorochemical emulsion.

Chubb C.

Perfluorochemicals provide a biologically inert system for oxygen transport to tissue. The purpose of the present study was to determine if a simple clean-up procedure could reverse the endocrine toxicity of a commercially produced perfluorochemical emulsion, Oxypherol-E.T. The clean-up procedure consisted of a combined resin and dialysis treatment. The endocrine toxicity of the untreated and treated perfluorochemical emulsions was tested by determining their effect on testosterone secretion by rat testes perfused in vitro. Rat testes perfused with untreated Oxypherol-E.T. secreted low amounts of testosterone. However, the treated Oxypherol-E.T. was an effective and nontoxic oxygen carrier for testes perfused in vitro. The results are significant because they suggest that the endocrine toxicity of Oxypherol-E.T. is caused by toxic contaminants and not the perfluorochemicals. Additional experiments revealed that the fluoride ion may be the primary toxic contaminant of Oxypherol-E.T. The data support the efficacy of perfluorochemicals as oxygen carriers for rat testes perfused in vitro.

PMID: 4084631 [PubMed - indexed for MEDLINE]


Fluoride 1985; 18(2):117-119

Implication of gluthathione in endemic fluorosis

Jeji J, Sharma R, Jolly SS, Pamnani S

Department of Medicine and Biochemistry, Government Medical College, Patiala, India

Summary: In a new approach to an understanding of the genesis of nonskeletal and skeletal fluorosis, glutathione content in blood was investigated. Thirty cases of fluorosis and forty controls (20 from fluorotic and 20 from nonfluorotic areas) were studied. In fluorotic subjects, blood gluthanthione concentration was significantly elevated. Urinary hydroxyproline and serum alkaline phosphatase data were also correlated. It appears that the persistent stress of the F- ion demands a protective redox maintainer and that glutathione fulfills the needs.


Fluoride 1985; 18(1):41-46

Effects of fluoride on rabbits fed low calcium diet

M Tsuchida and F Yanagisawa

Medical Research Institute, Tokyo Medical and Dental University, Tokyo, Japan

Summary: Rabbits were fed a low Ca diet (Ca:0.4%) or a normal Ca diet (CA1.6%) for 8 weeks starting 5 weeks after birth. Subsequently they were given 0, 5, and 15 mg F/kg intraperitoneally. Decrease in serum total Ca and Ca++ and delay in recovery as well as increase in the serum glucose level were more marked in the low Ca group than in the normal Ca counterpart. F- was retained in serum for a long time and urinary excretion was markedly decreasd in the low Ca group. That changes in the toxicity and metabolism of F- occur when the diet is low in Ca was confirmed.


Fluoride 1985; 18(1):53-61

Effect of fluoride on soft tissus in vertebrates (a review)

PA Monsour and BJ Kruger

Department of Oral Biology and Oral Surgery, Physiology Building, University of Queensland, St. Lucia, Queensland, Australia

[The authors summarize data relating to the Endocrine (adrenals, thyroid and parathyroid), Urinary, Digestive, Cardiovascular, Central Nervous, and Respiratory systems; as well as Some Selective tissues (muscle, skin, and collagen). 79 references.]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=4003773&dopt=Abstract

Anesth Analg 1985 Jun;64(6):563-9

Sex differences in halothane metabolism and hepatotoxicity in a rat model.

Plummer JL, Hall PM, Jenner MA, Cousins MJ.

This study was designed to investigate sex differences in halothane metabolism and hepatotoxicity in the hypoxic rat model. Phenobarbital-induced male and female rats were anesthetized with 1% halothane in 14% oxygen for two hours. Female rats were found to metabolize halothane by the oxidative pathway to a similar extent as males, but the extent of metabolism by the reductive pathway was less in females. All male rats exposed under these conditions developed confluent centrilobular hepatic necrosis. Females were less susceptible than males to the hepatotoxic effect of halothane, with responses ranging from no hepatic injury to confluent centrilobular necrosis limited to within a few cells of the central veins. This lesser susceptibility was not, however, solely due to the lesser extent of reductive metabolism in females, as lowering the inspired oxygen concentration to 12% increased the extent of reductive metabolism but did not increase the severity of the hepatic injury.

PMID: 4003773 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2997219&dopt=Abstract

J Biol Chem 1985 Nov 25;260(27):14671-6

Disruption of phosphatidylserine translocation to the mitochondria in baby hamster kidney cells.

Voelker DR.

Phosphatidylserine synthase is found predominantly in the microsomal fraction, and phosphatidylserine decarboxylase is found predominantly in the mitochondrial fraction of baby hamster kidney (BHK-21) cells. This segregation of enzymes of phosphatidylserine metabolism allows serine metabolism to phosphatidylserine and phosphatidylethanolamine to be used as an indicator of the intracellular movement of phosphatidylserine. After BHK-21 cells were pulse-labeled with [3H]serine, phosphatidylserine was efficiently labeled, and subsequently 40-50% of this radiolabeled lipid turned over to form phosphatidylethanolamine during a 7.5-h chase. Treatment of cells with NaN3 plus NaF or cycloheximide at the end of the pulse labeling period markedly inhibited the rate and extent of phosphatidylserine turnover during the chase period. The inhibition of phosphatidylserine turnover could not be attributed to inhibition of either phosphatidylserine decarboxylase or phosphatidylserine exchange protein activity. Subcellular fractionation of the BHK-21 cells demonstrated that cells poisoned with NaN3 plus NaF accumulated phosphatidylserine in the microsomal fraction relative to unpoisoned cells. The results indicate that metabolic energy is required for the transport of phosphatidylserine to the mitochondria.

PMID: 2997219 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3863758&dopt=Abstract

FEBS Lett 1985 Oct 28;191(2):181-5

Fluoroaluminates activate transducin-GDP by mimicking the gamma-phosphate of GTP in its binding site.

Bigay J, Deterre P, Pfister C, Chabre M.

Fluoride activation of the cGMP cascade of vision requires the presence of aluminum, and is shown to be mediated by the binding of one A1F-4 to the GDP/GTP-binding subunit of transducin. The presence of GDP in the site is required: A1F-4 is ineffective when the site is empty or when GDP beta S is substituted for GDP. This sensitivity to the sulfur of GDP beta S suggests that A1F-4 is in contact with the GDP. Striking structural similarities between A1F-4 and PO3-4 lead us to propose that A1F-4 mimics the role of the gamma-phosphate of GTP.

PMID: 3863758 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=4067544&dopt=Abstract

J Forensic Sci 1985 Oct;30(4):1206-9

Effect of sodium fluoride on cholinesterase activity in postmortem blood.

Baselt RC, Shaw RF, McEvilly R.

Thirty-two postmortem blood specimens, with and without sodium fluoride as preservative, were analyzed for cholinesterase activity by the Michel method. The fluoridated specimens, which contained from 0.7 to 31 mg/mL (average 6.3) of sodium fluoride, were found to exhibit cholinesterase activities that were 5 to 59% (average 25%) lower than the duplicate unfluoridated specimens. We concluded that, while this decrease is quite significant, a fluoridated postmortem blood specimen may be used for the measurement of cholinesterase activity when a non-fluoridated specimen is unavailable.

PMID: 4067544 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2992121&dopt=Abstract

Toxicol Appl Pharmacol 1985 Sep 15;80(2):199-205

Changes in adrenal function as a possible mechanism for elevation of serum glucose by a single large dose of fluoride.

Suketa Y, Asao Y, Kanamoto Y, Sakashita T, Okada S.

Serum glucose was elevated immediately after ip administration of a single large dose of fluoride (NaF 35 mg/kg) to rats. Moreover, elevation of serum glucose following ip administration of 35 mg/kg of fluoride to rats was suppressed by adrenalectomy, dibenamine, or propranolol, but not by thyroid-parathyroidectomy. The elevation of serum glucose was associated with enhancement of glucose-6-phosphatase activities in liver and kidney in fluoride-treated rats.

PMID: 2992121 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=4067833&dopt=Abstract

J Environ Pathol Toxicol Oncol 1985 Sep-Oct;6(1):33-41

Effects of aluminum hydroxide on fluoride and calcium metabolism.

Spencer H, Kramer L, Osis D, Wiatrowski E.

In order to determine whether and to what extent aluminum affects the absorption of fluoride in man, a study of the effect of aluminum hydroxide on fluoride metabolism was carried out under strictly controlled dietary conditions. Relatively small amounts of aluminum hydroxide were used: 30 ml given three times daily, containing a total of 1.8 gm aluminum. Fluoride and calcium balances were determined in control studies and during the intake of aluminum hydroxide. The fluoride intake of approximately 4 mg/day was due to the fluoride content of the diet and the drinking water. A study was also carried out in patients with osteoporosis who received a high fluoride intake of approximately 50 mg/day of sodium fluoride therapeutically for osteoporosis. The intake of aluminum hydroxide was associated with a significant increase of the fecal fluoride and with a significant decrease of the net absorption of fluoride, by an average of 57%, irrespective of the intake of fluoride. The-plasma fluoride levels decreased by 41%. The fluoride balances were either negative or less positive. Relatively small amounts of aluminum hydroxide resulted in phosphorus depletion, in an increase of the urinary calcium, and in negative calcium balances.

PMID: 4067833 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2994568&dopt=Abstract

Arch Biochem Biophys 1985 Sep;241(2):447-52

Response of superoxide anion production by guinea pig eosinophils to various soluble stimuli: comparison to neutrophils.

Yamashita T, Someya A, Hara E.

The effect of various soluble stimuli on the superoxide production by guinea pig eosinophils was studied in comparison to neutrophils. Phorbol myristate acetate, A23187, digitonin, NaF, concanavalin A (Con A), and cytochalasin E stimulated eosinophils and neutrophils to release O2-. The O2- production by these active agents, excluding Con A and cytochalasin E, was much greater in eosinophils than in neutrophils. Formyl-Met-Leu-Phe stimulated the O2- production in neutrophils but not in eosinophils. Neither histamine nor Val/Ala-Gly-Ser-Glu stimulated the O2- production in both types of leukocytes. A23187- or Con A-stimulated O2- production was greatly enhanced by cytochalasin B pretreatment in neutrophils but not in eosinophils. Lineweaver-Burk analysis of NADPH oxidase in particulate fractions showed that eosinophils possessed the same Km values as neutrophils and greater Vmax values than neutrophils, suggesting that eosinophils have a similar, but more active, O2- -generating enzyme system than neutrophils.

PMID: 2994568 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2994645&dopt=Abstract

Biochem Biophys Res Commun 1985 Aug 30;131(1):146-51

Effects of fluoride on retinal rod outer segment cGMP phosphodiesterase and G-protein.

Cook NJ, Nullans G, Virmaux N.

The effects of fluoride on ROS phosphodiesterase and G-protein have been studied using membrane-free extracts. When G-protein was present NaF, at millimolar concentrations, stimulated PDE activity however, in a G-protein free extract, cGMP hydrolysis was inhibited by high fluoride concentrations. Fluoride was also found to profoundly inhibit the ability of G-protein to bind a GTP analogue, GTP gamma S, both in the presence and absence of rhodopsin. Aluminium greatly modified these effects of fluoride on PDE and G-protein. The possibility that fluoride activates PDE through its effect on G-protein is discussed.

PMID: 2994645 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2991235&dopt=Abstract

J Biol Chem 1985 Aug 5;260(16):9081-4

Photoreceptor GTP binding protein mediates fluoride activation of phosphodiesterase.

Stein PJ, Halliday KR, Rasenick MM.

In this report, we show that fluoride activates dark-adapted rod outer segment phosphodiesterase, and that this activation is mediated, in analogy with adenylate cyclase, through a GTP binding protein. The GTP binding protein is released from dark-adapted rod outer segment membranes by exposure to fluoride and subsequent centrifugation. The 39-kilodalton subunit of the GTP binding protein, released from the membrane by this procedure, exhibits altered susceptibility to limited trypsin proteolysis, identical to that seen when hydrolysis-resistant GTP analogs are bound to that subunit. Repeated exposure of dark-adapted rod outer segment membranes to fluoride and subsequent centrifugation results in maximal activation of the membrane-bound phosphodiesterase. Thus, activation of phosphodiesterase by fluoride in the dark appears similar to fluoride activation of adenylate cyclase.

PMID: 2991235 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=4017997&dopt=Abstract

Environ Res 1985 Aug;37(2):461-74

Toxicity of sodium fluoride to the postnatally developing rat kidney.

Daston GP, Rehnberg BF, Carver B, Kavlock RJ.

The adult rat kidney is an important target organ for sodium fluoride; however, the toxicity of fluoride to the developing kidney is unknown. This study examined renal function following NaF exposure during the first 4 weeks after birth. Sprague-Dawley rats received a single ip injection of 0, 30, or 48 mg/kg NaF on postnatal Day 1, 8, 15, or 29. Alterations in renal function, histology, and morphology were determined 24, 48, and 120 hr after exposure. Measurements of renal function included urine volume, osmolality, the ability to concentrate urine during water deprivation, urinary pH, and chloride content. Rats were then sacrificed and their kidneys processed for observation by light microscopy. Some minor alterations in renal function were observed in the three youngest age groups after NaF exposure. These changes included decreased body weight after treatment with 30 or 48 mg/kg NaF but increased kidney-body weight ratio in the 48 mg/kg group on Day 1; decreased urinary pH in both dose groups after treatment on Day 1 or 8; increased urinary volume 120 hr after treatment on Day 8; and decreased chloride excretion in the 48 mg/kg group 24 hr after injection on Day 1. None of these effects was severe. In contrast to these results, marked renal toxicity was observed in postweaning rats treated on Day 29. The NaF exposure resulted in increased kidney weight and kidney/body weight ratio, profound diuresis, decreased urinary osmolality, and decreased ability to concentrate urine during water deprivation. Urinary chloride excretion was decreased for the first 2 days after NaF exposure, then increased in water-deprived rats 120 hr after treatment. Glucosuria and hematuria were present for 2 days after treatment with 48 mg/kg. Histological lesions were apparent in the proximal tubules of the treated Day 29 rats. Thus, the kidney of the suckling rat is largely unresponsive to NaF toxicity. Renal sensitivity increases abruptly after weaning in the Day 29 rat.

PMID: 4017997 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3880289&dopt=Abstract

No Abstract available

J Toxicol Clin Exp 1985 Jul-Aug;5(4):239-47

[Nephrotoxicity of sodium fluoride. Effect of aluminum sulfate]

[Article in French]

Kessabi M, Braun JP.

PMID: 3880289 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3850775&dopt=Abstract

Can J Cardiol 1985 Jul-Aug;1(4):288-93

Alterations in the cardiac adenylate cyclase activity in hypothyroid rat.

Daly MJ, Dhalla NS.

Adenylate cyclase activity of the washed particles from the ventricles of rats made hypothyroid by propylthiouracil (P.T.U.) treatment was studied in the absence or presence of different concentrations of catecholamines, guanylimido-diphosphate (GppNHp) and NaF. The washed particles preparation of hypothyroid rat displayed higher basal adenylate cyclase activity in comparison to that in the euthyroid animal. Fluoride stimulation was unaltered but GppNHp stimulation was markedly depressed over a wide range of concentrations in the hypothyroid heart washed particles. Epinephrine stimulation in the presence of GppNHp was altered only at 10(-5) to 10(-4)M concentrations. Depressed responsiveness of cardiac adenylate cyclase to GppNHp and epinephrine was also found in washed particles of thyroidectomized rats. Depression of GppNHp or epinephrine response in hypothyroid animals was reversed 48 hours after T3 administration. In contrast to the washed particulate preparation, no depressions in the responses of adenylate cyclase to GppNHp or epinephrine were seen in the purified sarcolemmal membranes from P.T.U. induced hypothyroid or thyroidectomized rat hearts. It is proposed that altered guanine nucleotide binding or altered guanine nucleotide binding protein-catalytic subunit interaction in the adenylate cyclase system may be an underlying mechanism of depressed positive inotropic action of catecholamines in the hypothyroid state.

PMID: 3850775 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2994759&dopt=Abstract

Biokhimiia 1985 Jul;50(7):1067-75

[Phosphoprotein phosphatases from cell nuclei of the bovine spleen: physico-chemical properties]

[Article in Russian]

Reziapkin VI, Leonova LE, Komkova AI.

The physico-chemical properties of phosphoprotein phosphatase (EC 1.3.1.16) from bovine spleen cell nuclei were investigated. The enzyme was shown to possess a wide substrate specificity and to catalyze dephosphorylation of phosphocasein, ATP, ADP and p-nitrophenylphosphate (pNPP). The Km values for ATP, ADP and pNPP are 0.44, 0.43 and 1.25 mM, respectively. The molecular weight of the enzyme as determined by gel filtration on Sephadex G-75 and electrophoresis in polyacrylamide gel of different concentrations is approximately 33 000. SDS-polyacrylamide gel electrophoresis revealed two protein bands with Mr 12 000 and 18 000. The enzyme molecule predominantly contains acidic amino acid residues, two free SH-groups and two disulphide bonds. Phosphoprotein phosphatase is a glycoprotein with the carbohydrate content of about 22%, and has an additional absorption maximum at 560 nm. The enzyme is competitively inhibited by ammonium molybdate (Ki = 0.37 microM) and non-competitively by sodium fluoride (Ki = 1.3 mM). Incubation of phosphoprotein phosphatase with 2 mM phenylmethylsulfonylfluoride (PMSF) for 25 hours resulted in a approximately 46% loss of the enzyme activity. Ammonium molybdate, sodium fluoride and PMSF reversibly inhibit the enzyme. Modification of aminoacid SH-groups, NH2-groups and histidine led to a decrease of the enzyme activity. Incubation of phosphoprotein phosphatase with [gamma-33P]ATP resulted in the incorporation of 0.33 mol of 33P per mol of the enzyme. The mechanism of the enzyme-catalyzed hydrolysis of the phosphoester bond is discussed.

PMID: 2994759 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3992658&dopt=Abstract

Tsitologiia 1985 Feb;27(2):153-6

[Ultracytochemical study of adenylate cyclase localization in the adenohypophysis of rats]

[Article in Russian]

Vostrikov VM.

Using an electron cytochemical method and adenylylimidodiphosphate (AMP--PNP) as substrate, the localization of adenylate cyclase activity was determined in the rat's adenohypophysis. This activity was discovered in the perinuclear space, in the canaliculi of the endoplasmic reticulum and Golgi complex, in mitochondria, on the external surface of the plasma membrane. In sinusoidal capillaries, the reaction product was localized on the plasma membrane, in perinuclear space, endoplasmic reticulum and mitochondria. The addition of isoproterenol and sodium fluoride to the incubation medium led to a rise in adenylate cyclase activity.

PMID: 3992658 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2411094&dopt=Abstract

Acta Endocrinol (Copenh) 1985 Jul;109(3):315-9

Divergent effects on LH and FSH synthesis and release from intact female rat pituitary glands in vitro by methylxanthines, cyclic AMP derivatives and sodium fluoride.

Jenner AA, de Koning J, Tijssen AM, van Rees GP.

FSH release from the female rat pituitary gland consists of an LH-like, LRH-dependent component and an autonomous, inhibin-sensitive component. It was investigated whether cyclic AMP mediated FSH release. BrcAMP, theophylline, MIX or NaF stimulated LH release but inhibited FSH release and synthesis. Although dbcAMP had no inhibitory effect on FSH release, it partly reversed the inhibitory action of theophylline. In view of previous and the present results it is concluded that cyclic AMP may mediate the LRH-dependent LH and FSH release and, through a separate pathway, may mediate the inhibition of autonomous FSH release by the ovarian protein inhibin.

PMID: 2411094 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2990464&dopt=Abstract

Biochem Biophys Res Commun 1985 Jun 28;129(3):664-70

Adenylate cyclase activity and cyclic AMP production in the outer and inner zones of the adrenal cortex.

Mikami K, Nishikawa T, Strott CA.

It has been reported that cells isolated from the inner zone of the guinea pig adrenal cortex fail to have a steroidogenic response to ACTH. To further explore this, adenylate cyclase activity of membrane particles and cAMP production by cells prepared from the inner and outer adrenocortical zones were determined. The cAMP response to ACTH and forskolin was similar for cells from both zones. Basal adenylate cyclase activity was significantly higher in the inner zone; and while absolute responses to ACTH, GppNHp, GTP, NaF, and forskolin were greater for the inner zone, relative responses were similar for the two zones. These observations suggest that the inner zone of the guinea pig adrenal cortex may have a defect in ACTH action at a step(s) beyond cAMP formation.

PMID: 2990464 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3926611&dopt=Abstract

No Abstract Available

Fortschr Med 1985 Jun 20;103(23):634-6

[Diagnosis of pulmonary emphysema. Analysis of the expiratory partial pressure curves of the gases O2, CO2, He and SF6]

[Article in German]

Worth H.

PMID: 3926611 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=4039939&dopt=Abstract

Biochem Pharmacol 1985 Jun 1;34(11):2013-7

Streptozotocin-induced diabetes and hormone sensitivity of adenylate cyclase in rat myocardial sarcolemma, aorta and liver.

Srivastava AK, Anand-Srivastava MB.

Adenylate cyclase activity was investigated in myocardial sarcolemma, aorta particulate fractions, and liver plasma membranes from control and 5-day streptozotocin-induced diabetic rats. The basal adenylate cyclase activity was increased in heart sarcolemma from diabetic rats, whereas the extent of stimulation by glucagon, dopamine, isoproterenol, epinephrine, sodium fluoride and forskolin was decreased markedly. The decreased responsiveness was associated with a decrease in Vmax but not in the activation constant. In contrast, GTP stimulated adenylate cyclase in control and diabetic myocardial sarcolemma to the same extent. In addition, the basal adenylate cyclase activity was not altered significantly in aorta particulate fraction of liver plasma membranes from diabetic rats, but the stimulation of adenylate cyclase by catecholamines and forskolin (in the case of aorta) and by adenosine, glucagon, NaF and forskolin (in the case of liver) was diminished markedly. These data suggest that, in streptozotocin-induced diabetes, the responsiveness of adenylate cyclase to various hormones and agents (fluoride and forskolin) which act through receptor-independent mechanisms is decreased.

PMID: 4039939 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=4000107&dopt=Abstract

Mol Pharmacol 1985 Jun;27(6):630-3

The slow rate of inhibition of acetylcholinesterase by fluoride.

Froede HC, Wilson IB.

We measured the rate of reaction of fluoride with acetylcholinesterase using a stopped flow apparatus for measurements on the millisecond time scale with phenylacetate as a chromogenic substrate. We found that the second order rate constant is 5 X 10(3) liters/mol/sec, which is very slow for a small symmetric ion; it is 3-4 orders of magnitude smaller than for the substrates acetylcholine, acetylthiocholine, and phenylacetate. The slowness of this reaction suggests that fluoride does not find a preexisting binding site but must create one, probably by breaking and reforming hydrogen bonds. With hydrolysis measurements made on the usual time scale, we found kcat = 7.5 X 10(5) min-1 and KM = 2.0 mM. We also found that fluoride enhances substrate inhibition and that with low phenylacetate concentration the per cent inhibition is independent of substrate concentration.

PMID: 4000107 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2408622&dopt=Abstract

Biochem Pharmacol 1985 May 15;34(10):1639-45

The influence of cellular ATP levels on receptor-mediated endocytosis and degradation of asialo-glycoproteins in suspended hepatocytes.

Tolleshaug H, Kolset SO, Berg T.

Receptor-mediated endocytosis in suspended hepatocytes was studied in conjunction with ATP levels of the cells, which were decreased by the use of metabolic inhibitors. The receptor system studied was the asialo-glycoprotein receptor, and multiple aspects of the endocytic pathway were examined: binding of ligand, internalization, intracellular transport and proteolysis. Moderate concentrations of the inhibitors (e.g. 30 microM rotenone or 200 microM iodoacetamide) produced only a transient decline in the ATP levels of the cells. Two to four times higher concentrations reduced the ATP levels to about 1/10 of control cells. At low levels of ATP (less than 30% of controls) the uptake ceased completely after 10-20 min. Moderate reductions brought about by rotenone reduced the uptake roughly in proportion to the ATP levels; iodoacetamide and sodium fluoride had little influence on the energy production by the cells, but the rate of asialo-glycoprotein uptake was reduced to a small fraction of controls. The effect of rotenone on the rate of uptake was mainly due to a lower rate of internalization of occupied receptors; the half-time for internalization of surface-bound ligand was increased from 2.9 to 6.2 min in the presence of 42 microM rotenone. The binding capacity of the cell surface was also somewhat lower. There was no degradation of the asialo-glycoproteins which were taken up by cells treated with high concentrations of rotenone or iodoacetamide. This was shown to be due to a low rate of transport of the endocytosed protein into those endosomes (at density 1.15 g/ml in a sucrose gradient) which were delivering their contents to the lysosomes; coincidentally, there was an accumulation of ligand in light endosomes (density 1.11 g/ml), in which the ligand appears immediately after endocytosis.

PMID: 2408622 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=4040041&dopt=Abstract

Mol Cell Endocrinol 1985 May;40(2-3):129-36

Opposite effects of ethanol on the activation of adenylyl cyclase in human corpus luteum membranes.

Rojas FJ, Asch RH.

The influence of an acute exposure to ethanol on adenylyl cyclase activity in membrane fractions prepared from human corpus luteum was investigated. Ethanol up to a concentration of 5% (v/v) was without effect on basal luteal adenylyl cyclase activity, but markedly potentiated stimulation of NaF and hCG in a dose-dependent manner. In contrast, ethanol progressively inhibited forskolin stimulation at the same range of ethanol concentrations. Maximal NaF and hCG responsiveness of adenylyl cyclase activity was observed at 5% ethanol and reached values 80% and 100% higher than controls without ethanol, respectively. However, at the same ethanol concentration, forskolin-stimulated enzymatic activity was reduced by 40% relative to controls. Equilibrium binding studies involving [125I]hCG interaction with luteal membranes in the presence of the concentration of ethanol showing maximal hCG responsiveness indicated that ethanol slightly affected (15% increase) the hCG binding compared to controls, without any appreciable change on the Kd for the hormone. This minor effect of ethanol on gonadotropin binding sites contrasted greatly with the extent at which ethanol maximally potentiated the gonadotropin-stimulated adenylyl cyclase. GTP was found to be less effective than GMP-P(NH)P in sustaining ethanol potentiation, suggesting that ethanol is unlikely to act by inhibiting GTPase activity. These data indicate that the acute effects of ethanol inhibit forskolin-stimulated adenylyl cyclase at concentrations potentiating stimulatory effects of NaF and of hCG, and that the synergistic interaction of ethanol and gonadotropin stimulation of adenylyl cyclase is, at least in part, due to an increase in the functional coupling of the occupied hCG-receptor complex with the components of the enzyme system.

PMID: 4040041 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3856773&dopt=Abstract

N Z Med J 1985 Mar 27;98(775):207

Sodium fluoride as an oral carcinogen.

Sutton PR.

Publication Types:

PMID: 3856773 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3888030&dopt=Abstract

Ann Otol Rhinol Laryngol 1985 Mar-Apr;94(2 Pt 1):103-7

Otospongiosis and sodium fluoride. A blind experimental and clinical evaluation of the effect of sodium fluoride treatment in patients with otospongiosis.

Bretlau P, Causse J, Causse JB, Hansen HJ, Johnsen NJ, Salomon G.

The effect of sodium fluoride treatment in patients with otospongiosis has been evaluated blindly in a morphological and microchemical element analysis of otospongiotic specimens together with a prospective clinical double-blind, placebo-controlled study. The results show that using the calcium/phosphorus ratio as an indication for bone maturity, the sodium fluoride treatment can stabilize otospongiotic lesions in retaining calcium relative to phosphorus. The clinical double-blind, placebo-controlled study of 95 patients showed a statistically significant worse deterioration of the hearing loss in the placebo group than in the active treated (40 mg sodium fluoride daily) group, supporting the view that sodium fluoride can change otospongiotic, active lesions to more dense, inactive otosclerotic lesions. We have postulated in the past that the actual mechanism of the cochlear loss is toxic enzymes produced by histiocytes at the periphery of the microfoci, and it may be that sodium fluoride has some effect on these enzymes.

Publication Types:

PMID: 3888030 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2987516&dopt=Abstract

J Mol Cell Cardiol 1985 Feb;17(2):133-43

Separation and reconstitution of regulatory and catalytic components of heart adenylate cyclase.

Panchenko MP, Grigorian GYu, Svitina-Ulitina IV, Avdonin PV, Tkachuk VA.

Ion-exchange chromatography of rabbit heart adenylate cyclase solubilized with lubrol PX results in two peaks of activity, AC I and AC II, differing in their sensitivity to guanylylimido-diphosphate [Gpp(NH)p], NaF and cholera toxin. AC I is activated 4- to 5-fold by Gpp(NH)p, 10- to 20-fold by NaF and 3- to 4-fold by cholera toxin. AC II is insensitive to Gpp(NH)p and cholera toxin, but is activated 2-fold by the fluoride. The differences in the regulatory properties of AC I and AC II are probably due to the unequal distribution of the N-protein, the regulatory component of adenylate cyclase, in the preparations. Addition of the N-protein, obtained by thermoinactivation of AC I, to AC II results in restoration of the enzyme sensitivity to Gpp(NH)p as well as in an increase of the stimulating effect of NaF. It is shown that the lag-period observed during adenylate cyclase stimulation by Gpp(NH)p is due to the slow transition of the N-protein into an activated conformation. This Gpp(NH)p-activated N-protein interacts with the catalytic component of adenylate cyclase without any lag-period. Addition of GTP to the Gpp(NH)p-activated soluble adenylate cyclase complex leads to a decrease of the enzymatic activity. This process presumably occurs via substitution of Gpp(NH)p for GTP in the N-protein with subsequent hydrolysis of GTP and not by exchange of the N-protein-Gpp(NH)p complex for the N-protein-GTP complex within the catalytic component of adenylate cyclase.

PMID: 2987516 [PubMed - indexed for MEDLINE]


Fluoride 1985; 18(3):146-149

Effect of fluoride on total lipid, cholesterol and triglyceride levels in liver of albino rabbits

Singh JP*, Shashi *, Thapar SP **

* Department of Zoology, Punjabi University
** Department of Anatomy, Government Medical College, Patiala, India

Summary: White albino rabbits received subcutaneous injections containing 0, 5 and 10 mg NaF/kg body weight in distilled water for three and one-half months and were sacrificed. The liver was analyzed for total lipids, cholesterol and triglycerides. The decrease in the concentration of total lipids and cholesterol in the livers of rabbits consuming fluoride in water was proportional to the increase in fluroide intake. The decrease in liver cholesterol and triglyceride content was statistically significant in 10 mg group.


Fluoride 1985; 18(3):157-162

Effects of ventilatory conditions on deposition of NaF in isolated rabbit lungs

Ichinohe S, Mita M, Tsunoda H

Department of Hygiene and Public Health, School of Medicine, Iwate Medical University, Morioka Japan

Summary: The effects of tidal volume and respiratory frequency on the deposition of NaF aerosol particles were studied using lungs isolated from 20 rabbits. Total lung deposition decreased with increases in tidal volume and respiratory flow rate and was in the range of 20-80% when the reciprocal of the respiratory flow rate was 0.05-0.5 sec/ml. Deposition of aerosol particles in various lung lobes had a 1:1 ratio with respect to the weight of each lobe. The deposition was especially high on the right middle lobe and markedly decreased with increases in respiratory flow rate.


Fluoride 1985; 18(4):216-220

F- effect on calcium and phosphate content in femur of the pregnant rat and on calcium transfer through the placenta

L Stosser and R Heinrich

Department of Preventive Dentistry, Faculty of Stomatology, Medical Academy of Erfurt, Germany.

Summary: Pregnant Wistar rats, which had received distilled water or water to which 100 ppm F- was added were decapitated at two intervals during pregnancy in order to determine the calcium, phosphate and fluroide content of the femur. Especially the calcium content of the bones obviously reveals the influence of fluoride on the mineral metabolism. A decrease in the calcium content, due to pregnancy, is apprent only in control animals. In fluoride-loaded animals the calcium content remained constant. Furthermore, the phosphorus content of the bones seems to be elevated in the fluoride group. No effect of fluoride on the transport of calcium through the placenta was found.


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3967057&dopt=Abstract

Biol Neonate 1985;47(1):54-60

Lipolytic activity of renal cortex during ontogenetic development in rats.

Hohenegger M, Brezina M, Tesarik E.

The lipolytic activity of rat kidney cortex was investigated in newborn and adult rats. Two peaks of lipolytic activity could be detected at pH 5.0 and 8.4, respectively. Lipase activity at pH 5.0 is completely inhibited by 0.2 M sodium fluoride and can be stimulated by norepinephrine (10 micrograms/ml). Full activity is already present in 5-day-old rats. The response to sodium fluoride and norepinephrine is identical in newborn and adult animals. Lipase activity at pH 8.4 is inhibited up to 85% by 0.6 M sodium chloride. Activity is very low in 5-day-old rats and increases during maturation. This lipase can be stimulated by heparin (100 micrograms/ml) by about 10-25% in newborn and adult animals.

PMID: 3967057 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2988524&dopt=Abstract

Biomed Biochim Acta 1985;44(2):341-3

Fluoride ions increase collagenase production by rabbit synovial fibroblasts.

Jendryczko A, Drozdz M.

Ionic fluoride is taken up by rabbit synovial fibroblasts in culture. The uptake was accompanied by an increased production of latent collagenase, and decreased activity of 5'-nucleotidase.

PMID: 2988524 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2580193&dopt=Abstract

Mech Ageing Dev 1985 Jan;29(1):19-28

Axoplasmic transport of substances in motoneuronal axons of the spinal cord in old age.

Frolkis VV, Tanin SA, Marcinko VI, Kulchitsky OK, Yasechko AV.

Seven to eight microliters of aqueous solution of L-[14C]Leucine (spec. act. 339 mCi/mmol) were introduced in the zone of ventral horn (L5-L6) of the spinal cord of adult (8-12 months) and old (26-28 months) rats. The radioactivity of various parts of the corresponding ventral roots was measured 1-2.5 h thereafter. Labelled substances (including protein) were found to migrate with fast flow in adult rats at the rate of 408 +/- 10.9 and 380 +/- 22 mm/24 h, respectively, as compared with 217 +/- 11.3 and 200 +/- 40 mm/24 h in old rats. The axoplasmic flow slows down in old rats with the increase of distance from the neuronal body. Uncoupling of oxidation and phosphorylation by the administration of 2,4-dinitrophenol, inhibition of glycolysis with NaF, hypoxemia produce more marked deceleration of axoplasmic flow in old rats, while small doses of NaF accelerate the flow, which correlates with the rise of cAMP in ventral roots. Sex steroids accelerate significantly the rate of axoplasmic flow. There is a marked increase in the rate due to the administration of estradiol dipropionate in old rats and due to testosterone propionate in adult animals. Changes in resting membrane potential and direct excitability thresholds of some muscles following colchicine blockade of axoplasmic transport are less marked in old rats that evidences for the weakening of neurotrophic control in old age.

PMID: 2580193 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2579564&dopt=Abstract

No Abstract available

Am J Otol 1985 Jan;6(1):38-42

Objective changes in trypsin, alpha 1-antitrypsin, and alpha 2-macroglobulin values as a result of sodium fluoride treatment in patients with otosclerosis.

Causse JR, Uriel J, Berges J, Bretlau P, Shambaugh GE Jr, Causse JB.

PMID: 2579564 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2997209&dopt=Abstract

J Biol Chem 1985 Nov 25;260(27):14477-83

Role of a guanine nucleotide-binding regulatory protein in the hydrolysis of hepatocyte phosphatidylinositol 4,5-bisphosphate by calcium-mobilizing hormones and the control of cell calcium. Studies utilizing aluminum fluoride.

Blackmore PF, Bocckino SB, Waynick LE, Exton JH.

Treatment of isolated hepatocytes with NaF produced a concentration-dependent activation of phosphorylase, inactivation of glycogen synthase, efflux of Ca2+, rise in cytosolic free Ca2+ ([Ca2+]i), increase in myo-inositol-1,4,5,-P3 levels, decrease in phosphatidylinositol-4,5-P2 levels, and increase in 1,2-diacylglycerol levels. These changes were evident within 1 min and maximum at 2-5 min. Maximum effects on Ca2+ efflux, [Ca2+]i, glycogen synthase, and phosphorylase were observed with 15 mM NaF, whereas myo-inositol-1,4,5-P3 and 1,2-diacylglycerol levels were maximally stimulated by 50 mM NaF. The levels of intracellular cAMP were decreased by NaF (up to 10 mM) in the absence or presence of glucagon (0.1-1 nM) or forskolin (2 microM). The effects of low doses of NaF (2-15 mM) to inhibit basal or glucagon-stimulated cAMP accumulation, mobilize Ca2+, activate phosphorylase, and inactivate glycogen synthase were all potentiated by AlCl3. This potentiation was abolished by the Al3+ chelator deferoxamine. These results illustrate that AlF4- can mimic the effects of Ca2+-mobilizing hormones in hepatocytes and suggest that the coupling of the receptors for these hormones to the hydrolysis of phosphatidylinositol-4,5-P2 to myo-inositol 1,4,5-P3 is through a guanine nucleotide-binding regulatory protein. This is because AlF4- is known to modulate the activity of other guanine nucleotide regulatory proteins (Ni, Ns, and transducin).

PMID: 2997209 [PubMed - indexed for MEDLINE]


Back to the top

Return to FAN's Pesticide Homepage