FLUORIDE ACTION NETWORK PESTICIDE PROJECT

Return to FAN's Pesticide Homepage

Return to Abstracts Page


Pineal Gland Abstracts: 1994

Note: the following is a limited selection of abstracts available at PubMed, Science Direct, and Toxnet.

Abstracts on the Pineal Gland by Year
-
2005
(Jan-June)
2004
2003
2002
2001
2000
1999
1998
1997
1996
1995
1994
1993
1992
1991
1990
Up to 1989

 

http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7869231&dopt=Abstract

J Pineal Res. 1994 Sep;17(2):86-93.

Photoperiod and melatonin affect testicular growth in the marsh rice rat (Oryzomys palustris).

Edmonds KE, Stetson MH.

Physiology and Anatomy Section, School of Life and Health Sciences, University of Delaware, Newark 19716.

Reproduction in rice rats is subject to photoperiodic control and the pineal gland mediates this effect. We examined the effects of the pineal gland hormone melatonin on testicular weight when administered via implants, injections, and infusions. Testicular weight was modified by photoperiod and the size of the melatonin implant. Twenty-millimeter implants suppressed testicular weight in rice rats housed on 12- and 16-hr photoperiods, while those housed on a 14-hr photoperiod were more sensitive to melatonin; in these animals 10- and 20-mm implants inhibited testicular weight. Melatonin implants also prevented rice rats from responding to a change in photoperiod with the appropriate alteration of testicular growth. Melatonin injections inhibited testicular growth when administered before lights out on LD 14:10, but not on LD 16:8. Morning injections had no effect on either photoperiod. Finally, 12-hr duration melatonin infusions inhibited testicular growth in pinealectomized rice rats on LD 16:8, while 6-hr duration infusions were without effect. These data show that the pineal, through the secretion of melatonin, is a phototransducing organ intimately involved in testicular growth in rice rats.

PMID: 7869231 [PubMed - indexed for MEDLINE]

 

http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7699308&dopt=Abstract

J Electron Microsc (Tokyo) 1994 Oct;43(5):307-17
Scanning electron microscopy and electron probe microanalysis studies of human pineal concretions.

Kodaka T, Mori R, Debari K, Yamada M.

Department of Oral Anatomy, School of Dentistry, Showa University, Tokyo, Japan.

The calcareous concretions of human pineal bodies were investigated with scanning electron microscopy and electron probe microanalysis. The initial concretions measuring 5-7 microns in diameter may have started at the calcified pinealocytes. They grew appositionally forming concentric laminations, and then the simple calcospherulites over 20 microns occasionally aggregated with each other. Some of them became numerous spherulite-aggregated concretions. Others individually grew with scallop-shaped concentric laminations at intervals of 0.05-1 microns and became lobated calcospherulites up to 0.5 mm. The concretions over 0.5 mm were formed by their attachments. The major elements were Ca and P, while traces of S, Mg, and Na were detected. In the calcification and crystallization values, the center of the concretions over 50 microns was significantly higher than the periphery, while there were no differences among the centers and also among the peripheries. The Ca and P amounts in the center were 30.8% and 14.2% by weight and the Ca/P molar ratio was 1.68; thereby the sand-grain-shaped crystals may be nearly hydroxyapatite, as reported previously.


PMID: 7699308 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7943614&dopt=Abstract

Brain Dev 1994 May-Jun;16(3):249-52

Precocious puberty
in a case with probable Angelman syndrome.


Young C, Wang PJ, Tsai WY, Shen YZ.

Department of Pediatrics, National Taiwan University Hospital, Taipei, ROC.

The authors report a 9-year-old girl with mid-facial hypoplasia, maxillary hypoplasia, prognathia, microbrachycephaly, mouth opening and protruding tongue. She also had psychomotor retardation such as mental retardation and speech delay. Frequent laughter fits and seizure disorder was also noted. Although the high resolution chromosome study failed to demonstrate any deletion of chromosome 15q, the clinical picture was compatible with Angelman syndrome. Breast development at the age of six and rapid progression of bone age was noted at follow up. After a series of examinations, the diagnosis of gonadotropin-dependent precocious puberty was made. MRI of brain revealed an intermediate cyst in the pituitary gland and slightly enlarged pineal gland. However, serum alpha-fetoprotein and beta-HCG were undetectable and the size of the pineal gland remained the same at the 1-year follow-up. She was treated with long-acting GnRH analogue and valproic acid. The combination of precocious puberty and Angelman syndrome has not been reported before and such association needs further experience for clarification.

PMID: 7943614 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7962639&dopt=Abstract

J Clin Pathol. 1994 Aug;47(8):771-2.

Testicular seminoma in a patient with pineal germinoma.

Peat DS, Trowell JE.

Department of Histopathology, Ipswich Hospital.

A case is reported of a 30 year old man with a testicular seminoma. He had presented 16 years previously with a pineal germinoma, followed two years later by intracranial metastases. This is an unusual occurrence of double pathology in the germ cell line.

PMID: 7962639 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7922457&dopt=Abstract

Brain. 1994 Aug;117 ( Pt 4):683-703.

Agnosia, alexia and a remarkable form of amnesia in an adolescent boy.

Vargha-Khadem F, Isaacs E, Mishkin M.

Neurosciences Unit, University of London, UK.

Childhood cases of global anterograde amnesia, visual agnosia or alexia without agraphia, either alone or in any combination, are extremely rare. Here we report the case of a male adolescent, Neil (a pseudonym), who consequent to a pineal tumour began to exhibit all three disorders in the presence of normal verbal intelligence. The most surprising aspect of Neil's case, however, is his ability to retrieve postmorbid memories through the act of writing without being able to provide any oral account of the content of his written reports. His memory retrieval thus has some of the character of 'automatic writing'. This evidence pointing to Neil's possession of a dissociated form of episodic memory presents a new challenge to our understanding of the organization of memory and of the cerebral systems underlying it.

PMID: 7922457 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7960471&dopt=Abstract

Int J Neurosci. 1994 May;76(1-2):71-9.

The relationship of pineal calcification to cerebral atrophy on CT scan in multiple sclerosis.

Sandyk R, Awerbuch GI.

NeuroCommunication Research Laboratories, Danbury, CT 06811.

Calcification is a known morphological feature of the pineal gland. The mechanisms underlying the development of pineal calcification (PC) are elusive although there is experimental evidence that calcification may be a marker of the past secretory activity of the gland and/or of degeneration. The increased incidence of PC with aging suggests that it may reflect cerebral degenerative changes as well. In a recent Editorial in this Journal it was proposed that the pineal gland is implicated in the pathogenesis of multiple sclerosis (MS). Cerebral atrophy, which can be demonstrated on CT scan, is a common feature of MS resulting from demyelination and gliosis. If PC is a marker of a cerebral degenerative process, then one would expect a higher incidence of calcification of the gland in patients with cerebral atrophy compared to those without cerebral atrophy. To test this hypothesis, we studied the incidence of PC on CT scan in a cohort of 48 MS patients, 21 of whom had cerebral atrophy. For the purpose of comparison, we also assessed the incidence of choroid plexus calcification (CPC) in relation to cerebral atrophy. PC was found in 42 patients (87.5%) and its incidence in patients with cerebral atrophy was significantly higher compared to the incidence in patients without cerebral atrophy (100% vs. 77.7%; p < .025). In contrast, CPC was unrelated to cerebral atrophy or to PC thus supporting the notion of a specific association between the pineal gland and the pathogenesis of MS.(ABSTRACT TRUNCATED AT 250 WORDS)

PMID: 7960471 [PubMed - indexed for MEDLINE]

From TOXNET

NTIS Technical Report (NTIS/PB94-151784) 1994 Jan;:196 pp.

Status report on potential human health effects associated with power frequency electric and magnetic fields. Reporting period: June 1992-June 1993.

Creasey W, Phil D, Goldberg R, McAna J

Information Ventures, Inc., Philadelphia, PA.

This report reviews articles published between June 1992 and June 1993 and ongoing research on the potential adverse health effects from exposure to power frequency electric and magnetic fields (EMFs). It reviews the epidemiology and general human health effects of EMF, and relevant research findings in the areas of animal tumor studies, experimental studies of biological, developmental, immunological, neurobehavioral and physiological effects, and cell-level research. Appendices cover state and local initiatives regarding regulation of EMF exposure, and studies of exposure mitigation. More than half of the major epidemiologic studies this year reported weak associations between EMF exposure and cancer, principally leukemia, but all suffer from the small numbers of cases involved. Data from animal tumor studies have been as contradictory as in previous years with respect to the activity of EMF as a tumor promoter. While a majority of the reported studies of the biological effects of EMF describe positive findings, these effects are not completely consistent, and results obtained by one group cannot always be replicated by other researchers. The most convincing effects are mild behavioral disturbances, altered heart rate, changes in daily rhythms of melatonin production by the pineal, effects on calcium transport, and modifications in gene expression.

Publication Types: TECHNICAL REPORT
Title Abbreviation: NTIS Technical Report (NTIS/PB94-151784)

http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7853139&dopt=Abstract

J Pineal Res. 1994 Aug;17(1):17-9.

Melatonin concentrations in pineal organ culture are suppressed by sera from tumor-bearing mice.

Leone AM, Skene D.

Department of Physical Sciences, Wellcome Research Laboratories, Kent, U.K.

The melatonin rhythm is significantly attenuated in a wide range of human and animal tumor types. Since surgical removal of the tumor has been shown to restore this rhythm, we hypothesized that a plasma borne tumor-associated factor (TAMF) could be responsible. A population of mice were injected with tumor cells and sequentially killed and bled over the following 9 days, i.e., to the maximal state of tumor growth. Pooled serum from the different collection days was added to an established pineal organ culture system, and melatonin concentrations measured. A highly significant correlation between melatonin concentrations and the stage of tumor growth was seen with maximal inhibition occurring at day 9 (P < 0.01). These findings support our hypothesis and may help to explain the mechanism whereby melatonin rhythmicity is suppressed in cancer patients.

PMID: 7853139 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7845626&dopt=Abstract

Neurosci Lett. 1994 Sep 26;179(1-2):60-4.

The adult human cerebellum is a target of the neuroendocrine system involved in the circadian timing.

Fauteck JD, Lerchl A, Bergmann M, Moller M, Fraschini F, Wittkowski W, Stankov B.

Institute of Anatomy, Westfalische Wilhelms-Universitat, Munster, Germany.

In an investigation aimed at comprehensive mapping of the adult human brain with respect to receptor sites for the pineal hormone melatonin, we consistently observed specific binding in the cerebellum. Autoradiography and in vitro binding analysis with 125I-labeled melatonin were used to examine the location and the properties of these binding sites. In all cerebellar lobes, highest-density specific binding was localized to the external zone of the molecular layer. The binding was rapid, saturable, displaceable, specific and of high affinity. Physiological concentrations of NaCl decreased the affinity, while presence of calcium ions promoted it. The non-hydrolyzable GTP analog, GTP gamma S, inhibited binding in a dose-dependent manner and provoked a shift towards low affinity. The results strongly suggest that these binding sites may be functional melatonin receptors, and indicate that the adult human cerebellum is a target of melatonin, the pineal hormone involved in the control of the circadian timing.

PMID: 7845626 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7947318&dopt=Abstract

Pediatr Neurosurg 1994;21(1):91-103; discussion 104

No Astract available

Pineal region tumors in childhood. Experience at the Hospital for Sick Children. 1983.


Hoffman HJ, Yoshida M, Becker LE, Hendrick EB, Humphreys RP.

Publication Types:
PMID: 7947318 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8077674&dopt=Abstract

J Immunol. 1994 Sep 15;153(6):2671-80.

Activation of human monocytes by the pineal hormone melatonin.

Morrey KM, McLachlan JA, Serkin CD, Bakouche O.

Department of Molecular Pharmacology and Biologic Chemistry, Northwestern Universit
y Medical School, Chicago, IL 60611.

To determine the effects of the pineal hormone melatonin on human monocytes, human monocytes were activated by different concentrations of melatonin. Above the activation threshold of 5 x 10(-11) M, melatonin was able to induce the cytotoxicity of human monocytes, the secretion of IL-1, and the production of reactive oxygen intermediates. Melatonin and LPS seemed to have a synergistic effect on human monocyte activation. Indeed, below their respective monocyte activation threshold (5 x 10(-11) M and 0.625 ng/ml), melatonin (10(-12) M) in association with LPS (0.2 ng/ml) was able to induce cytotoxicity, IL-1 secretion, and reactive oxygen intermediates production. Melatonin alone at 10(-12) M or LPS alone at 0.2 ng/ml did not activate monocytes. Furthermore, melatonin was able to prime the monocytes for a subsequent activation by LPS. When monocytes were activated by LPS (0.25 ng/ml) at the time that they were plated and then activated by melatonin (10(-12) M) 8 h later, no IL-1 secretion and no cytotoxicity were detected. However, when the cells were first activated by melatonin (10(-12) M), and then 8 h later by LPS (0.25 ng/ml), IL-1 secretion and monocyte cytotoxicity were observed. Above its monocyte activation threshold, melatonin induces both cell-associated IL-1 alpha and IL-1 beta activities. Below this activation threshold, i.e., at 10(-12) M, melatonin does not induce the cell-associated IL-1 alpha and IL-1 beta activities, but does induce the mRNA for both IL-1 (alpha and beta). It seems that melatonin activates monocytes through protein kinase C. These data suggest that melatonin activates monocytes and induces their cytotoxic properties, along with the IL-1 secretion.

PMID: 8077674 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7968351&dopt=Abstract

Brain Res Mol Brain Res. 1994 Jul;24(1-4):145-52.

A 6.1 kb 5' upstream region of the mouse tryptophan hydroxylase gene directs expression of E. coli lacZ to major serotonergic brain regions and pineal gland in transgenic mice.

Huh SO, Park DH, Cho JY, Joh TH, Son JH.

Laboratory of Molecular Neurobiology, Cornell University Medical College, W.M. Burke Medical Research Institute, White Plains, NY 10605.

Tryptophan hydroxylase (TPH) catalyzes the first step of serotonin biosynthesis in serotonergic neurons and neuroendocrine cells. Serotonin influences diverse vital physiological functions and is thought to play an important role in several human psychiatric disorders. To localize DNA element(s) important for serotonergic tissue-specific expression of TPH, 6.1 kb of the 5' flanking region of the mouse TPH gene was fused to the coding region of the E. coli lacZ gene, and expression of the resulting fusion gene was analyzed in transgenic mice. The 6.1 kb of 5' flanking sequence was able to direct the expression of a lacZ reporter gene to serotonergic tissues in six lines of transgenic mice. A high level of lacZ expression in transgenic mice carrying the fusion gene was detected in the pineal gland as well as a moderate level of lacZ expression in serotonergic brain regions such as the median and dorsal raphe nuclei, the nuclei raphe magnus and raphe pallidus. In contrast, a smaller 5' flanking sequence of 1.1 kb directed no detectable serotonergic tissue-specific lacZ expression in five lines of transgenic mice. These results presented in this paper suggest first that DNA elements critical to serotonergic tissue-specific expression reside between -6.1 kb and -1.1 kb of 5' flanking region of the mouse TPH gene, but second that this region confers a restricted tissue-specific expression.

PMID: 7968351 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7960369&dopt=Abstract

Int J Epidemiol. 1994 Jun;23(3):458-64.

International incidence of childhood brain and spinal tumours.

Stiller CA, Nectoux J.

Department of Paediatrics, University of Oxford, UK.

BACKGROUND. Intracranial and spinal cord tumours are the second most frequent type of childhood cancer after leukaemia, accounting for around 20% of cases in many regions of the world, yet there have been few studies of their incidence by histological type and subsite.
METHODS. Age-specific and age-adjusted incidence rates were calculated from data in the study, 'International Incidence of Childhood Cancer', co-ordinated by the International Agency for Research on Cancer.
RESULTS. The highest age-adjusted incidence, 31.4 per million, was observed in the Nordic countries, and rates between 24 and 27 per million were found in most other predominantly white Caucasian populations. In the US, black children had a significantly lower incidence (21.7) than whites (26.4). Lower rates were seen in South America, Africa and Asia, the lowest being those for Chinese populations, and for blacks in Africa, both below 15 per million. Among white populations, astrocytomas were the commonest histological type, often with an incidence of at least 10 per million, followed by medulloblastomas, 5-6 per million, and ependymomas, 2-4 per million. In other regions with lower incidence rates, these three types accounted for similar proportions of the total. Black children in the US had a higher incidence of craniopharyngiomas than whites and there was an unusually high incidence of pineal tumours in Japan, 0.9 per million compared with 0.3-0.4 in many other countries.
CONCLUSIONS. The low recorded total incidence in developing countries may be partly due to underascertainment. Differences in total incidence or in relative frequencies of particular histological types between Western countries and Japan and between ethnic groups in the US suggest a substantial contribution of genetic predisposition in their aetiology.

PMID: 7960369 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7969427&dopt=Abstract

Nature. 1994 Nov 3;372(6501):94-7.

Pinopsin
is a chicken pineal photoreceptive molecule.

Okano T, Yoshizawa T, Fukada Y.

Department of Pure and Applied Sciences, College of Arts and Sciences, University of Tokyo, Japan.

In avian pinealocytes, an environmental light signal resets the phase of the endogenous circadian pacemaker that controls the rhythmic production of melatonin. Investigation of the pineal phototransduction pathway should therefore reveal the molecular mechanism of the biological clock. The presence of rhodopsin-like photoreceptive pigment, transducin-like immunoreaction, and cyclic GMP-dependent cation-channel activity in the avian pinealocytes suggests that there is a similarity between retinal rod cells and pinealocytes in the phototransduction pathway. We have now cloned chicken pineal cDNA encoding the photoreceptive molecule, which is 43-48% identical in amino-acid sequence to vertebrate retinal opsins. Pineal opsin, produced by transfection of complementary DNA into cultured cells, was reconstituted with 11-cis-retinal, resulting in formation of a blue-sensitive pigment (lambda max approximately 470 nm). In the light of this functional evidence and because the gene is specifically expressed only in the pineal gland, we conclude that it is a pineal photosensor and name it pinopsin.

PMID: 7969427 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7825825&dopt=Abstract

Ann N Y Acad Sci. 1994 Nov 25;741:46-9.

No Abstract available

The pineal gland as ontogenetic scanner of reproduction, immunity, and aging. The aging clock.

Pierpaoli W.

Neuroimmunomodulation Laboratory, Italian National Research Centers on Aging (INRCA), Ancona.

Publication Types: Review; Review, Tutorial

PMID: 7825825 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7983791&dopt=Abstract

Nippon Rinsho. 1994 Oct;52(10):2641-2.

[Rabson-Mendenhall syndrome]

[Article in Japanese]

Ando A.

2nd Department of Internal Medicine, Kobe University School of Medicine.

Rabson-Mendenhall syndrome was initially reported in 1956 by Rabson et al., who described three children with familial hyperplasia of pineal gland and diabetes mellitus. Characteristic features of this syndrome are low birthweight, thickened nails, hirsutism, acanthosis nigricans, dental precosity and dysplasia, polycystic ovary, abdominal proturbance, phallic enlargement and insulin resistant diabetes mellitus. Most patients die of ketoacidosis and intercurrent infection associating with extreme insulin resistance during mid-childhood. This syndrome appears to show autosomal recessive inheritance. Recent reports provide evidence that mutations in the insulin-receptor gene are, at least in pant, the cause of this syndrome, and that recombinant IGF-I (insulin-like growth factor-1) reduces hyperglycemia in patients of this syndrome.

Publication Types: Review; Review, Tutorial

PMID:
7983791 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7660855&dopt=Abstract

J Biol Regul Homeost Agents. 1994 Oct-Dec;8(4):126-9.

Role of the pineal gland in the control of macrophage functions and its possible implication in cancer: a study of interactions between tumor necrosis factor-alpha and the pineal hormone melatonin.

Lissoni P, Barni S, Tancini G, Brivio F, Tisi E, Zubelewicz B, Braczkowski R.

Division of Oncological Radiotherapy, San Gerardo Hospital, Monza, Milano, Italy.

Recent studies have shown the existence of reciprocal links between cytokine activity and immunomodulating neurohormones or neuropeptides. In particular, the pineal hormone melatonin (MLT) appears to influence IL-2 activity in cancer. The present study was performed to evaluate which interaction exists between MLT and another important cytokine, tumor necrosis factor-alpha (TNF), which is responsible for both antitumor cytolytic activity and cancer-related cachexia. In a first study, we analyzed MLT circadian rhythm under TNF administration (0.75 mg/day i.v. for 5 days) in 10 metastatic solid tumor patients. In a second study, we evaluated TNF serum levels in 10 metastatic solid tumor patients under therapy with MLT alone (20 mg/day orally in the evening for at least 1 month). In a third study, we have measured concomitantly daily serum levels of MLT and TNF in 30 patients with metastatic solid neoplasms. Nocturnal mean serum concentrations significantly increased in response to TNF injection. MLT therapy induced a significant decline in TNF mean values. Finally, patients with abnormally high MLT diurnal levels showed significantly lower TNF mean concentrations with respect to those with normal levels of the pineal hormone. This study, by showing the stimulatory effect of TNF on MLT secretion and the inhibitory action of MLT on TNF release, would suggest the existence of feed-back mechanisms operating between the pineal gland and TNF released from macrophages in human neoplasms.

PMID: 7660855 [PubMed - indexed for MEDLINE]


http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7964299&dopt=Abstract

J Endocrinol. 1994 Sep;142(3):475-84.

The development of melatonin-binding sites in the ovine fetus.

Helliwell RJ, Williams LM.

Rowett Research Institute, Bucksburn, Aberdeen, UK.

The pineal hormone, melatonin, is important in the timing of seasonal reproduction in the sheep. Melatonin of maternal origin readily crosses the placenta; its function in the fetal sheep is, however, unclear. To gain an insight into the role of melatonin in ovine development we have identified specific melatonin receptors throughout gestation using 2-[125I]iodomelatonin and quantitative in vitro autoradiography. Specific binding was found at the earliest time studied at 30 days of gestation, over the developing thyroid (term = 145 days). At 31 days of gestation specific labelling was found over the thyroid and pituitary glands, the spinal nerves, nasal cavity and developing bronchi. This binding was diminished by over 50% in the presence of 10(-4) M GTP gamma S (an analogue of guanosine triphosphate) indicating that the 2-[125I]iodomelatonin binding at this early stage of gestation represents a receptor coupled to a regulatory G-protein. By 40 days of gestation specific binding was found over the nasal epithelium, cochlear epithelium, regions of the brain, especially the hind brain and the vestibulocochlear and glossopharyngeal nerves, and both the pars distalis and pars tuberalis of the pituitary. As gestation proceeded, labelling over the pars distalis appeared to become more scattered in nature while that on the pars tuberalis remained consistent. Saturation studies of both the neuronal and pituitary binding sites at 121 days of gestation and in the newborn lamb revealed a single class of high-affinity binding sites with Kd values in the picomolar range. Also at 121 days of gestation, binding over the fetal pars tuberalis was diminished in a dose-dependent manner by GTP gamma S, again confirming that specific binding is indicative of a receptor coupled to a regulatory G-protein. These data demonstrate a potential for sensitivity to melatonin from early in gestation, as well as the developmentally specific expression of the melatonin receptor in certain tissues, and suggest a wider role for melatonin in ovine fetal development than previously considered.

PMID: 7964299 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7804849&dopt=Abstract

Brain Res. 1994 Sep 5;656(1):85-94.

Intracellular free Ca2+ in dissociated cells of the chick pineal gland: regulation by membrane depolarization, second messengers and neuromodulators, and evidence for release of intracellular Ca2+ stores.

D'Souza T, Dryer SE.

Program in Neuroscience, Florida State University, Tallahassee 32306-4075.

The regulation of intracellular free Ca2+ concentration was examined in single dissociated chick pineal cells using the fura-2 technique. Approximately 10% of cells examined exhibited spontaneous Ca2+ oscillations while the rest were quiescent. Application of salines containing 80 mM KCl evoked large increases in intracellular free Ca2+ that were dependent upon external Ca2+ ions. These responses were inhibited by 10 microM nifedipine indicating involvement of L-type Ca2+ channels. Application of the tumor promoter thapsigargin (2 microM) evoked increases in intracellular free Ca2+. These responses could be observed in the absence of external Ca2+ indicating mobilization of internal stores. In the absence of external Ca2+, the responses to thapsigargin gradually decayed due to depletion of internal Ca2+ pools. A subsequent exposure to saline containing 5.8 mM CaCl2 caused a rapid increase in intracellular Ca2+ that was consistently larger than the peak response to thapsigargin. Application of 100 nM vasoactive intestinal peptide (VIP), a neurohormone that stimulates melatonin secretion from pineal cells, induced a sustained increase in intracellular free Ca2+ in a subpopulation of cells. In a small number of cells, VIP evoked Ca2+ oscillations. Approximately half of the cells examined showed no response to VIP. Application of 200 microM norepinephrine, which inhibits melatonin secretion from the chick pineal, had no effect on intracellular free Ca2+ in any quiescent or spontaneously oscillating cells. Application of 5 mM 8-Br-cAMP evoked sustained increases in intracellular Ca2+. Similar effects were obtained with the phosphodiesterase inhibitors papaverine (50 microM) or isobutylmethylxanthine (100 microM). Application of 200 nM forskolin, an activator of adenylate cyclase, evoked increases in intracellular free Ca2+ that could be detected in the presence of 10 microM nifedipine. The responses to forskolin gradually decayed in Ca(2+)-free external salines due to depletion of intracellular Ca2+ stores. Subsequent exposure to external Ca2+ caused a rapidly developing increase in intracellular Ca2+ that was larger than the peak response to forskolin. These results indicate that the regulation of intracellular free Ca2+ in chick pineal cells is complex. These cells exhibit Ca2+ oscillations and can mobilize both external and internal Ca2+ pools. Agents that increase intracellular cAMP cause mobilization of internal Ca2+ stores, possibly secondary to effects on other second messenger systems. Chick pineal cells, like many other cell types, possess mechanisms to allow for refilling of depleted internal Ca2+ stores. These results suggest new mechanisms for the regulation of melatonin synthesis and secretion and possible sites of action for the intrinsic circadian oscillator.

PMID: 7804849 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7522930&dopt=Abstract

Brain Res. 1994 Jul 18;651(1-2):160-8.

Pineal nitric oxide synthase: characteristics, adrenergic regulation and function.

Lin AM, Schaad NC, Schulz PE, Coon SL, Klein DC.

Section on Neuroendocrinology, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892.

Available studies indicate that the adrenergic stimulation of pineal cyclic GMP production involves stimulation of guanylyl cyclase activity by nitric oxide (NO) derived from arginine. This line of investigation was extended in the present study. Using a highly sensitive microassay, it was found that pineal NO synthase activity is present at levels approximately 30% of those in the cerebellum, that approximately 95% of enzyme activity is cytoplasmic, that the enzyme is Ca2+/calmodulin-dependent and that enzyme activity is inhibited by the arginine analog NG-nitro-L-arginine methyl ester (L-NAME). Norepinephrine treatment of intact glands in culture increased [3H]citrulline formation from [3H]arginine. This treatment also increased the formation of an NO-like compound, indicating that NO synthase activity in the intact gland is elevated by adrenergic stimulation. Studies on the effects of inhibition of NO synthase activity indicated that treatments known to inhibit NO synthase activity and the adrenergic stimulation of cyclic GMP accumulation did not inhibit adrenergic stimulation of pineal cyclic AMP, N-acetyltransferase activity or melatonin production. These observations support the hypothesis that NE stimulation of pineal cyclic GMP accumulation involves stimulation of a Ca2+/calmodulin-sensitive form of NO synthase, resulting in enhanced accumulation of NO; and, that although NO appears to play a role in the adrenergic stimulation of pineal cyclic GMP accumulation, it does not appear to play a critical role in the adrenergic stimulation of cyclic AMP, N-acetyltransferase activity or melatonin production.

PMID: 7522930 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8034747&dopt=Abstract

J Cell Biol. 1994 Jul;126(2):485-94.

Expression and functional interaction of hepatocyte growth factor-scatter factor and its receptor c-met in mammalian brain.

Jung W, Castren E, Odenthal M, Vande Woude GF, Ishii T, Dienes HP, Lindholm D, Schirmacher P.

Institute of Pathology, University Hospital, Mainz, Germany.

Hepatocyte growth factor-scatter factor (HGF-SF) is a pleiotropic cytokine with mito-, morpho-, and motogenic effects on a variety of epithelial and endothelial cells. HGF-SF activity is mediated by the c-met protooncogene, a membrane-bound tyrosine kinase. Here, we demonstrate that both genes are expressed in developing and adult mammalian brains. HGF-SF mRNA is localized in neurons, primarily in the hippocampus, the cortex, and the granule cell layer of the cerebellum, and it is also present at high levels in ependymal cells, the chorioid plexus, and the pineal body. c-met is expressed in neurons, preferentially in the CA-1 area of the hippocampus, the cortex, and the septum, as well as in the pons. In the embryonic mouse, brain HGF-SF and c-met are expressed as early as days 12 and 13, respectively. Neuronal expression of HGF-SF is evolutionary highly conserved and detectable beyond the mammalian class. Incubation of septal neurons in culture with HGF-SF leads to a rapid increase of c-fos mRNA levels. The results demonstrate the presence of a novel growth factor-tyrosine kinase signaling system in the brain, and they suggest that HGF-SF induces a functional response in a neuronal subpopulation of developing and adult CNS.

PMID: 8034747 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7559104&dopt=Abstract

J Anat. 1994 Aug;185 ( Pt 1):1-49.

The harderian gland: a tercentennial review.

Payne AP.

Department of Anatomy, Glasgow University, Scotland, UK.

The harderian gland was first described in 1694 by Johann Jacob Harder (1656-1711). It occurs in most terrestrial vertebrates and is located within the orbit where, in some species, it is the largest structure. It may be compound tubular or compound tubuloalveolar, and its secretory duct is usually morphologically distinct only after leaving the substance of the gland to open on the surface of the nictitating membrane. The tubules of the gland are formed of a single layer of columnar epithelial cells surrounded by myoepithelial cells. The chief product(s) of the gland varies between different groups of vertebrates, and epithelial cells possess granules or vacuoles whose contents may be mucous, serous or lipid. In rodents, the gland synthesises lipids, porphyrins and indoles. In the case of lipid vacuoles, the gland is unusual in releasing these by an exocytotic mechanism. It is unclear whether the gland can act both as an exocrine and endocrine organ. There is control of gland structure and synthesis through a variety of humoral agents, including gonadal, thyroid and pituitary hormones; in addition there is a rich autonomic innervation and many neuropeptides have been identified. The proposed functions of the gland are remarkably diverse and include the gland being
(1) a source of 'saliva',
(2) a site of immune response,
(3) a photoprotective organ,
(4) part of a retinal-pineal axis,
(5) a source of pheromones,
(6) a source of thermoregulatory lipids,
(7) a site of osmoregulation, and
(8) a source of growth factors.
The gland is discussed in terms of its embryology and phylogeny, and in relation to ecological variables. Several goals of future research are identified.

Publication Types: Review; Review, Academic

PMID: 7559104 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7696900&dopt=Abstract

Eksp Klin Farmakol. 1994 Sep-Oct;57(5):3-7.

No Abstract available

[The participation of the epiphysis in the action of psychotropic agents]

[Article in Russian]

Arushanian EB.

Publication Types: Review; Review, Tutorial

PMID: 7696900 [PubMed - indexed for MEDLINE]