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Schulkin J. Mapping biochemical signals in the brain. Neurotox Res 2004; 6:xv-xxi. [PMID: 15614982 DOI: 10.1007/bf03033446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Jay Schulkin
- Department of Physiology and Biophysics, Georgetown University School of Medicine, Washington, DC 20007, USA.
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2
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Abstract
More than 30 years ago, T-maze studies with progesterone indicated that sex hormones have the potential to act as a discriminative stimulus in rats. Despite these early positive findings, the interest in discriminative stimulus properties of sex hormones remained low; few studies were dedicated to the investigation of discriminative stimulus properties of hypothalamo-pituitary-gonadal axis hormones (i.e., LHRH, LH/FSH, sex steroids). Nevertheless, the few studies that were published showed some interesting, and often sex-dependent results. Applying various methodologies (T-, or Y-maze, two-lever drug discrimination, taste aversion procedures), it was found that not only progesterone but also the two other principal sex steroids estradiol and testosterone can serve as discriminative stimuli in rodents. In addition to these gonadal hormones, the hypothalamic peptide LHRH (having a key role in the neuroendocrine regulation of steroid release from the gonads) appears to generate discriminative stimulus properties. Interestingly, recent (but preliminary) studies in postmenopausal women suggest that estradiol (and possibly progesterone) may also function as a discriminative stimulus in human subjects.
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Affiliation(s)
- R De Beun
- Department of Behavioral Pharmacology, Novo Nordisk A/S, Måløv, Denmark
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3
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Feuvrier E, Aubert M, Malaval F, Szafarczyk A, Gaillet S. Opposite regulation by glucocorticoids of the alpha 1B- and alpha 2A-adrenoreceptor mRNA levels in rat cultured anterior hypothalamic slices. Neurosci Lett 1999; 271:121-5. [PMID: 10477117 DOI: 10.1016/s0304-3940(99)00483-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
In this study we investigated whether the expression of alpha1B- and alpha2A-adrenoreceptor mRNAs is differently modulated by glucocorticoids in rat cultured anterior hypothalamus slices. Using a semi-quantitative reverse transcription-polymerase chain reaction assay, the level of the alpha1B-adrenoreceptor mRNA was significantly reduced in slices cultured in steroid free-medium when compared with that measured in standard medium (i.e. containing basal adrenosteroid plasma concentrations). In contrast, the expression of the alpha2A-adrenoreceptor mRNA was markedly increased. Finally, the ratio of alpha1B- versus alpha2A-mRNA levels was about 1.7 and 0.7 in standard and steroid-free medium, respectively. These responses were completely reversed by supplementation with corticosterone. These findings provide the first evidence that in vitro glucocorticoids may regulate, in an opposite manner, the expression of the alpha1B-and alpha2A-adrenoreceptor mRNAs in the hypothalamus. This kind of regulation could be related to steroid-dependent changes in the noradrenergic control of neuroendocrine secretions.
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MESH Headings
- Animals
- DNA, Complementary/analysis
- Gene Expression Regulation/drug effects
- Glucocorticoids/pharmacology
- Hypothalamus/drug effects
- Hypothalamus/metabolism
- Organ Culture Techniques
- RNA, Messenger/biosynthesis
- RNA, Messenger/metabolism
- Rats
- Rats, Sprague-Dawley
- Receptors, Adrenergic, alpha-1/genetics
- Receptors, Adrenergic, alpha-1/metabolism
- Receptors, Adrenergic, alpha-2/genetics
- Receptors, Adrenergic, alpha-2/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
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Affiliation(s)
- E Feuvrier
- Cerebral Plasticity Laboratory, EP 628 CNRS, University of Montpellier 2, France
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4
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Calogero AE, Bagdy G, D'Agata R. Mechanisms of stress on reproduction. Evidence for a complex intra-hypothalamic circuit. Ann N Y Acad Sci 1998; 851:364-70. [PMID: 9668627 DOI: 10.1111/j.1749-6632.1998.tb09010.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- A E Calogero
- Department of Internal Medicine, University of Catania, Italy
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5
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Wetzel H, Wiesner J, Hiemke C, Benkert O. Acute antagonism of dopamine D2-like receptors by amisulpride: effects on hormone secretion in healthy volunteers. J Psychiatr Res 1994; 28:461-73. [PMID: 7897617 DOI: 10.1016/0022-3956(94)90004-3] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Amisulpride is a selective D2-like dopamine receptor antagonist with a high affinity for the cloned D2 and D3 receptors. At low doses it may improve depressive and negative schizophrenic symptoms whereas antipsychotic effects on positive schizophrenic symptomatology require higher dosages. Acute endocrine effects were studied for two doses of amisulpride with regard to the daytime secretion of prolactin, thyroidea stimulating hormone (TSH), growth hormone (GH), luteinizing hormone (LH) and cortisol. Amisulpride was administered i.v. to eight healthy male volunteers in a single-blind trial under a randomized cross-over, placebo-controlled design using doses of 20 mg or 100 mg, or saline. The drug was injected at 09:00 h, and plasma samples were withdrawn from 08:30 h to 16:00 h at intervals of 15 and 30 min, respectively. At both dosages, prolactin was significantly elevated to the eight- to ten-fold of baseline levels. Likewise, a significant 50% elevation of TSH concentrations with a trend to a greater increase under the 100 mg dose was observed. Plasma levels of LH and cortisol were not significantly affected by amisulpride. With regard to GH secretion, there was a trend to a decrease only with the 20 mg dose. These results indicate that the neuroendocrinological side-effect profile of acute amisulpride administration may be similar to conventional neuroleptics, and that there are only minor dose-dependent differential effects on hormone secretion in the dose range investigated.
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Affiliation(s)
- H Wetzel
- Department of Psychiatry, University of Mainz, F.R.G
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6
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Burgunder JM. Ontogeny of somatostatin gene expression in rat forebrain. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 1994; 78:109-22. [PMID: 7911743 DOI: 10.1016/0165-3806(94)90015-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
With hybridization histochemistry, somatostatin (SRIF) mRNA was detected in several neuronal populations of the basal diencephalon (anterior and posterior) and basal telencephalon (lateral) for the first time on the 14th day of gestation (E14). On E16, a large increase of the extent of expression was found in these populations. In addition, cells in the medial telencephalon and a few cells in the future allocortex also contained SRIF mRNA for the first time. In the prenatal period, the expression in the above populations continued to mature and individual nuclei with SRIF mRNA began to be recognizable. At birth, the overall pattern of SRIF gene expression was established but the ventral portions (hypothalamus, amygdala, allocortical areas) had higher levels of expression than the more dorsal ones (striatum and neocortex). Over the first 2 wk of life, this difference decreased and an adult-like pattern was found at postnatal day 21. We demonstrate that most of SRIF gene expression development takes place before birth. This description may serve as a basis for studies on the putative functions of SRIF during brain ontogeny.
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Affiliation(s)
- J M Burgunder
- Neurologische Klinik, Inselspital, University of Berne, Switzerland
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7
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Arai R, Jacobowitz DM, Deura S. Immunohistochemical localization of calretinin-, calbindin-D28k- and parvalbumin-containing cells in the hypothalamic paraventricular and supraoptic nuclei of the rat. Brain Res 1993; 618:323-7. [PMID: 8374764 DOI: 10.1016/0006-8993(93)91284-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The localization of three calcium-binding proteins, calretinin, calbindin-D28k and parvalbumin, in the hypothalamic paraventricular and supraoptic nuclei of the rat was immunohistochemically examined on adjacent sections and their distribution patterns were compared. Overlap between the distribution of calretinin-immunoreactive cells and that of calbindin-D28k-immunostained cells was found in the rostrodorsal part of the supraoptic nucleus, and the caudoventral part of this nucleus contained predominantly calbindin-D28k-stained cells. Cells of the medial and lateral magnocellular subdivisions of the paraventricular nucleus were almost devoid of the calcium-binding proteins examined. No parvalbumin-immunostained cells were observed in either nucleus. This study provides a further characterization of cell bodies in the hypothalamic paraventricular and supraoptic nuclei.
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Affiliation(s)
- R Arai
- Department of Anatomy, Fujita Health University School of Medicine, Aichi, Japan
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8
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Blasquez C, Jégou S, Tranchand Bunel D, Fournier A, Vaudry H. Neuropeptide Y inhibits alpha-MSH release from rat hypothalamic slices through a pertussis toxin-sensitive G protein. Brain Res 1992; 596:163-8. [PMID: 1334775 DOI: 10.1016/0006-8993(92)91544-o] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The arcuate nucleus of the hypothalamus contains various types of peptidergic neurons. In particular, two distinct populations of neurosecretory neurons containing neuropeptide Y (NPY)- and alpha-melanocyte-stimulating hormone (alpha-MSH)-like immunoreactivity have been identified in the arcuate nucleus. Double-labeling immunocytochemical data have recently shown that NPY-containing fibers make synaptic contacts with proopiomelanocortin (POMC) immunoreactive neurons. We have thus investigated the possible effect of NPY on the release of alpha-MSH from rat hypothalamic slices in vitro, using the perifusion technique. NPY significantly inhibited KCl-stimulated alpha-MSH release in a dose-dependent manner. The inhibitory effect of NPY was mimicked by the Y2 agonist, NPY-(13-36), while the Y1 agonist, [Leu31,Pro34]NPY, was devoid of effect. Pretreatment of hypothalamic slices with pertussis toxin (PTX) blocked the inhibitory effect of NPY, suggesting that the action of NPY on POMC neurons is mediated through a PTX-sensitive G protein. These results support the notion that NPY may play a physiological role in the regulation of alpha-MSH release from hypothalamic neurons.
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Affiliation(s)
- C Blasquez
- European Institute for Peptide Research, CNRS URA 650, UA INSERM, University of Rouen, Mont-Saint-Aignan, France
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9
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Abstract
Support for the many relationships between thyroid hormones and brain function comes from both laboratory and clinical studies. Studies in laboratory animals provide convincing evidence for a neuroregulatory role of thyroid hormones in the brain, suggesting that they may affect behavior. This notion is supported by human studies which have revealed that the effects of thyroid hormones on brain function are most important during the development and maturation of the brain; thereafter, age does not seem to critically affect brain-thyroid hormone relationships.
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Affiliation(s)
- P T Loosen
- Department of Psychiatry, Vanderbilt University, Nashville, Tennessee
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10
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Abstract
The aim of this study was to examine, by use of a pre-embedding immunoperoxidase technique, the ultrastructural localization of galanin immunoreactivity in the external layer of the rat median eminence. Galanin immunoreactivity was only observed in axonal profiles. Immunoreactive fibers were found in contact with the following non-immunoreactive structures: (1) axonal profiles that contain dense granular vesicles and clear vesicles, (2) axonal profiles that contain predominantly clear vesicles, (3) glial cell bodies, and (4) processes of tanycytes. Labeled terminals were also observed in the proximity of the perivascular space of the portal vessels. The results suggest possible interactions between galanin-immunoreactive terminals and other terminals containing peptide and/or other transmitters in the external layer of the median eminence.
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Affiliation(s)
- R Arai
- Départment de Cytologie, CNRS UA 1199, Université Pierre et Marie Curie, Paris, France
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11
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Mulatero B, Fasolo A. Calcitonin gene-related peptide immunoreactivity in the hypothalamo-hypophysial system of the green frog, Rana esculenta. Gen Comp Endocrinol 1991; 81:349-56. [PMID: 1711493 DOI: 10.1016/0016-6480(91)90161-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The distribution of calcitonin gene-related peptide (CGRP) has been investigated in the hypothalamus of the frog Rana esculenta L. by means of different immunohistochemical techniques. A few immunopositive cell bodies and several fibers have been demonstrated in the preoptic area and in the caudal hypothalamus. Some CGRP-like fibers were also recognized in the outer zone of the median eminence. Simultaneous double immunofluorescence methods showed CGRP-like immunoreactivity to be often contiguous to substance P-like positive structures, but separated from them.
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Affiliation(s)
- B Mulatero
- Dipartimento di Biologia Animale, Università Torino, Italy
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12
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Toivonent M, Tuomainen P, Rauhala P, Männistö PT. Effects of cysteamine pretreatment and hypothalamic periventricular nucleus lesion on the cold-stimulated thyrotropin responses to intracerebroventricular 5-hydroxytryptamine in male rats. J Neuroendocrinol 1990; 2:485-92. [PMID: 19215378 DOI: 10.1111/j.1365-2826.1990.tb00437.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Abstract The hypothalamic somatostatinergic system was devitalized in male rats by intracerebroventricular (icv) cysteamine (CSH) pretreatment (250 mug/rat/day into the third ventricle) on 4 consecutive days or by a limited lesion of the hypothalamic periventricular nucleus (PeVNx). The acute effect of icv serotonin (5-HT) on the cold-stimulated thyrotropin (TSH) and prolactin responses were studied in these animals. The experiments were performed 24 h after the last saline or CSH infusions and 7 days after the sham- or PeVN-lesions. CSH and PeVNx decreased the hypothalamic somatostatin content by 44% to 57% and 19% to 28%, respectively. PeVNx did not affect hypothalamic thyrotropin-releasing hormone content. 5-HT infusion (9 mug/rat icv) into the anterior third ventricle elevated, although not significantly, TSH levels in both saline- or CSH-pretreated rats. 5-HT infusion into the anterior third ventricle did not affect TSH in sham-operated rats. However, 5-HT augmented the cold-stimulated TSH levels after PeVNx compared to sham-lesion. Inversely, 5-HT infusion (9 mug/rat) into the posterior third ventricle inhibited TSH secretion irrespective of the pretreatment or lesion. The inhibitory action of 5-HT on TSH was significantly suppressed by CSH. 5-HT infusions elevated serum prolactin levels irrespective of the infusion site, pretreatment or lesion. 5-HT infusion into both the anterior and the posterior third ventricle decreased rectal temperature in saline-pretreated, sham- and PeVN-lesioned rats. The hypothermie effect of 5-HT was weakened by CSH. The hypothalamic levels of noradrenaline, dopamine and their metabolites were not significantly affected by CSH and PeVNx. 5-HT infusion into the anterior third ventricle decreased hypothalamic dopamine content in both saline- and CSH-pretreated rats. However, such an effect was not seen in sham- or PeVN-lesioned animals. Although CSH is an inhibitor of dopamine-beta-hydroxylase, this activity was not reflected in serum TSH or prolactin levels. The results support our hypothesis of the site-dependent action of icv 5-HT or TSH secretion. The elevation of TSH levels may arise from the inhibition of somatostatin release from rostral anterior hypothalamus. The inhibition of TSH secretion may result from the inhibition of thyrotropin-releasing hormone release from more caudal periventricular structures of the hypothalamus.
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Affiliation(s)
- M Toivonent
- Research Unit of Neurobiology, University of Helsinki, Finland
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13
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Rubin RT, Poland RE, Lesser IM. Neuroendocrine aspects of primary endogenous depression. X: Serum growth hormone measures in patients and matched control subjects. Biol Psychiatry 1990; 27:1065-82. [PMID: 2111183 DOI: 10.1016/0006-3223(90)90044-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
To determine the extent of dysregulation of growth hormone (GH) secretion in endogenous depression, we measured nocturnal serum GH concentrations and GH responses to thyrotropin-releasing hormone (TRH, gonadotropin-releasing hormone (LHRH), and dexamethasone administration in 40 Research Diagnostic Criteria primary, definite endogenous depressives and 40 individually matched normal control subjects. Compared with their controls, the patients showed no difference in basal nocturnal GH concentrations or in GH responses to TRH or LHRH. The GH measures were not significantly related to the other endocrine measures reported previously, including dexamethasone suppression test status. None of the diagnostic schemes for endogenous/melancholic depression which we studied was significantly related to the GH measures in the patients. Of the other subject and symptom variables, the mood depression factor of the Hamilton depression scale and the performance difficulty factor of the Beck depression inventory were moderately negatively correlated with the nocturnal GH measures. These findings suggest that, in contrast to the previously reported hypothalamopituitary-adrenal cortical and thyroid axis abnormalities in our patients, GH secretion was relatively normal. Patients with more severe depressed mood and greater difficulty accomplishing tasks did have moderately lower nocturnal GH values.
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Affiliation(s)
- R T Rubin
- Department of Psychiatry, Harbor-U.C.L.A. Medical Center, Torrance 90509
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14
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Toivonen M, Männistö PT. Complex actions of serotonergic agonists on cold-stimulated TSH secretion in male rats. Eur J Pharmacol 1990; 180:91-102. [PMID: 2142094 DOI: 10.1016/0014-2999(90)90596-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The effects of serotonergic activation on cold-stimulated thyrotropin (TSH) and prolactin secretion were studied in male rats. Peripheral injections of both 8-hydroxy-2-(di-n-propylamino)-tetralin (8-OH-DPAT), a 5-HT1A receptor agonist, and 1-(3-chlorophenyl)piperazine (m-CPP), a 5-HT1 agonist, decreased TSH levels. The action of 8-OH-DPAT was antagonized by (+/-)-pindolol, which is known to have 5-HT1 antagonist activity, but not by metergoline or ketanserin. The action of m-CPP was antagonized by ketanserin but not by metergoline. TSH levels were not affected by a 5-HT3 receptor agonist, 2-methyl-5-HT, or by a 5-HT3 antagonist, MDL 72222. Infusion of 8-OH-DPAT into the anterior third ventricle increased TSH levels; 5-HT tended to increase TSH levels, but the effect was not significant. Inversely, infusion of 5-HT, 8-OH-DPAT or m-CPP into the posterior third ventricle decreased TSH levels. The action of 5-HT was counteracted by metergoline, ketanserin and (+/-)-pindolol. Unexpectedly, m-CPP infusion into the anterior third ventricle also inhibited TSH secretion. The prolactin-elevating effects of 5-HT, 8-OH-DPAT and m-CPP were neither consistent nor site-specific. In conclusion, stimulation of both 5-HT1 and 5-HT2 receptors may inhibit TSH secretion, but the exact mechanism underlying the site-dependent action of 5-HT and 8-OH-DPAT on TSH secretion remains to be identified.
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Affiliation(s)
- M Toivonen
- Research Unit of Neurobiology, University of Helsinki, Finland
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Toivonen M, Tuomainen P, Männistö PT. Effects of hypothalamic paraventricular nucleus lesion on the cold-stimulated TSH responses to 5-HT in male rats. ACTA PHYSIOLOGICA SCANDINAVICA 1990; 139:233-40. [PMID: 1972606 DOI: 10.1111/j.1748-1716.1990.tb08916.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The effects of lesion of the hypothalamic paraventricular nuclei (PVNx), the main thyrotrophic area, on the cold-stimulated thyrotropin (TSH) responses to intracerebroventricular (i.c.v.) 5-HT were studied in male rats. PVNx significantly attentuated the cold-stimulated TSH levels, but significantly affected neither hypothalamic thyrotropin-releasing hormone nor somatostatin content. Serum T3 levels were significantly decreased 8 days after PVNx. Irrespective of the lesion (sham or PVNx), 5-HT infusion (9 micrograms per rat) into the posterior third ventricle attenuated markedly the cold-stimulated TSH levels, whereas infusion into the anterior third ventricle did not. Bilateral 5-HT infusions (2 micrograms per side) into the hypothalamic dorsomedial nuclei significantly decreased serum TSH, but bilateral infusions into the posterior hypothalamic nuclei were without effect. Sham-lesion and PVNx decreased serum prolactin levels without affecting the stimulation of prolactin secretion by i.c.v. 5-HT. These results suggest that the inhibitory effect of i.c.v. 5-HT on TSH secretion and its stimulatory action on prolactin secretion are only partially dependent on the PVN.
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Affiliation(s)
- M Toivonen
- Research Unit of Neurobiology, University of Helsinki, Finland
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Corio M, Thibault J, Peute J. Topographical relationships between catecholamine- and neuropeptide-containing fibers in the median eminence of the newt, Triturus alpestris. An ultrastructural immunocytochemical study. Cell Tissue Res 1990; 259:561-6. [PMID: 1969331 DOI: 10.1007/bf01740784] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Dopaminergic and peptidergic nerve fibers were simultaneously demonstrated with a double-labeling technique at the ultrastructural level. The first antibody, raised against tyrosine hydroxylase, was applied during the preembedding phase and visualized with the peroxidase method. The second antibody, raised against one of the peptides met-enkephalin, somatostatin or gonadotropin-releasing hormone (GnRH), was applied to the ultrathin sections and visualized with gold-labeled goat anti-rabbit IgG. The fibers of both categories were present in the zona externa of the median eminence, frequently contacting the basal lamina of the portal vessels. In addition, topographical relationships between different types of nerve fibers were observed in the perivascular areas, although there were no morphological signs of synaptic specializations. Using serial sections, it could be established that one GnRH-fiber contacted both a dopaminergic fiber and a fiber immunoreactive for met-enkephalin. The observations support earlier physiological data concerning the regulation of the hypothalamo-hypophyseal axis, with special emphasis on the release of neurohormones in the median eminence of the newt.
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Affiliation(s)
- M Corio
- CNRS, Centre de Neurochimie, Strasbourg, France
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