Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01178 (oxytocin)
 15,767 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Central neurotransmitter and/or neuromodulator candidates reported to affect gastric acid secretion are: (excitatory) acetylcholine, thyrotropin releasing hormone, GABA, oxytocin; (inhibitory) noradrenaline, adenosine, bombesin, calcitonin-gene related peptide, corticotropin releasing factor, beta-endorphin, neurotensin, neuropeptide Y, insulin-like growth factor II and prostaglandins. Regulation of gastric acid secretion by central administration of these substances in experimental animals such as rats and dogs are briefly reviewed, and central inhibitory mechanisms of this function are discussed based on our studies with noradrenaline and bombesin. Roles of hypothalamic nuclei such as the ventromedial nucleus and the lateral hypothalamus in regulation of autonomic nerve activities are also described as an introductory note.
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PMID:[Central neurotransmitters and regulation of gastric acid secretion]. 198 Jun 59

Recent results have demonstrated altered corticotropin-releasing factor (CRF)-41 content of the neurointermediate lobe (NIL) of the pituitary gland in response to various manipulations including osmotic stimulation. This study was undertaken to determine whether changes in CRF-41 content of the NIL are accompanied by changes in intensity of CRF-41-like immunoreactivity (CRF-41-LI) of neurosecretory neurones of the hypothalamus in response to osmotic stimulation. Wistar rats of both sexes given either tap water ad libitum, 2% NaCl solution, or access to tap water was limited to 20 min daily, for 7 days. Subsets of rats from each group were adrenalectomized (ADX) or treated with dexamethasone (DEX). Thirty-six hour before perfusion with fixative consisting of buffered formaldehyde and picric acid, animals received 75 micrograms colchicine i.c.v. Forty micrometer thick vibratome sections were stained for CRF-LI, arginine vasopressin (AVP-LI) and oxytocin (OXY-LI) using the avidin-biotin-peroxidase complex method. In response to both types of osmotic stimulation magnocellular neurones of the paraventricular (PVN) and supraoptic nuclei (SON) showed increased CRF-LI, AVP-LI and OXY-LI, while CRF-LI of parvocellular perikarya of the PVN decreased. The enhanced CRF-LI seemed to appear in a subset of magnocellular neurones with OXY-LI but not AVP-LI. Increased staining intensities were also observed in magnocellular neurones in ADX rats challenged osmotically. In contrast, systemic DEX administration, as well as implantation of DEX in the area on the SON, sharply attenuated CRF-LI but not AVP-LI or OXY-LI of magnocellular neurones in osmotically stimulated rats.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Oxytocinergic neurons in rat hypothalamus. Dexamethasone-reversible increase in their corticotropin-releasing factor-41-like immunoreactivity in response to osmotic stimulation. 211 29

Feedback inhibition of the adrenocortical axis by circulating glucocorticoids occurs at the pituitary and CNS sites. In the CNS, both hypothalamic and suprahypothalamic sites have been implicated as mediators of glucocorticoid feedback activity. In the present experiments, we have attempted to identify specific CNS regions mediating the feedback and to characterize which hypothalamic adrenocorticotropic hormone secretagogues are under glucocorticoid inhibitory control. Adrenalectomized rats were presented with a delayed feedback signal in the form of systemic infusion with corticosterone or dexamethasone. Hypophysialportal concentrations of corticotropin-releasing factor (CRF), arginine vasopressin (AVP), and oxytocin (OT) were determined before and during a hypotensive stressor in the face of varying levels of feedback. The rats were then killed, and the extent of total, type I, and type II corticosteroid receptor occupancy in hippocampus, hypothalamus, and amygdala was determined. The following observations were made: (1) increased hippocampal corticosteroid receptor occupancy was associated with suppressed adrenocorticotropic hormone secretagogue concentrations; (2) the major, significant predictor of initial (prehypotensive) concentrations of CRF, AVP, and OT was the extent of occupancy of hippocampal type II receptors, often in combination with occupancy of hippocampal type I or hypothalamic receptors; (3) secretion of CRF induced by hypotension was best predicted by hippocampal type I and type II receptor occupancy (stress-induced OT secretion was best predicted by hippocampal type II and hypothalamic receptor occupancy), and (4) the 'shape' of the hippocampal type II receptor occupancy versus initial AVP concentration curve suggested a nonlinear, threshold type of relationship, implying tight hippocampal regulation of AVP secretion.
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PMID:Glucocorticoid feedback inhibition of adrenocorticotropic hormone secretagogue release. Relationship to corticosteroid receptor occupancy in various limbic sites. 215 97

If we consider the chemical messengers in the central nervous system, there are about ten classic transmitters--the catecholamines, biogenic amines and amino acids--as opposed to over 50 different neuropeptides. These include previously well-established circulating hormones such as angiotensin, atrial natriuretic peptide, vasopressin and oxytocin, calcitonin and calcitonin gene related peptide (CGRP), the opioid family of peptides, gastrointestinal peptides, pituitary peptides and their releasing factors, and miscellaneous peptides such as the kinins, bombesin, gallanin, and others; all occur as neuropeptides in the brain. There is evidence supporting a role in central cardiovascular control for angiotensin, opioid peptides, substance P, neuropeptide Y, vasopressin, atrial natriuretic peptide, kinins, corticotropin releasing factor, bombesin, somatostatin, and some other peptides. They have been localized in brain areas known to be important for blood pressure regulation, and specific high-affinity peptide receptors have also been discovered. Upon central administration, these peptides produce cardiovascular effects, partly by interacting with other blood pressure-controlling neuroregulators, e.g. catecholamines and GABA. Central inhibition of brain peptide synthesis or interaction with competitive antagonists at the receptor site results in marked cardiovascular effects. Altered peptide levels and activity of synthesizing enzymes, as well as supersensitivity to the pressor action of some brain peptides, have been described in experimental models of hypertension. We are using angiotensin as a model peptide to study the peptidergic control of cardiovascular function.
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PMID:Peptidergic control of cardiovascular function: the angiotensin paradigm. 219 11

The chemical organization of the hypothalamic paraventricular nucleus (NPV) of the sheep was studied immunocytochemically by using antisera raised against oxytocin (OXY), ovine corticotropin releasing factor (CRF), somatostatin (SRIF), neurotensin (NT) and vasoactive intestinal polypeptide (VIP). Examination of immunocytochemically stained frozen, 30-40 microns thick, and paraffin serial, 6 microns thick, sections has shown that chemically specified subsets of neurons are not strictly demarcated anatomically and that OXY and SRIF or CRF and VIP are jointly expressed by certain subpopulations of neurons which are different from that producing both OXY and CRF.
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PMID:Coexistence of neuropeptides in the hypothalamic paraventricular nucleus of the sheep. 225 93

In this study we examined the effects of 2% saline loading (S), partial restriction of water consumption (R) or a combination of S or R with dexamethasone (DEX) treatment for 14 days on corticotropin releasing factor (CRF)-41 content of the neurointermediate lobe (NIL) and supraoptic nuclei (SON) of male Wistar rats. Arginine vasopressin (AVP) and oxytocin (OXY) contents of the NIL and SON were also assayed as well as plasma corticosterone, ACTH, [Na+] and [Cl-] concentrations. S or R for 14 days resulted in an increase in CRF-41 content and a concomitant drop in AVP and OXY contents of the NIL. Dexamethasone treatment enhanced the effect of S but not of R on NIL CRF-41 content. Dexamethasone treatment abolished the decrease in the AVP content and partially reversed the decrease in the OXY content of the NIL in response to S but not in response to R. No changes were observed in CRF-41, AVP and OXY content of the SON. Unstressed plasma corticosterone concentrations were not changed in S rats but were elevated in R rats; DEX did not prevent this elevation. Plasma ACTH concentrations were low in all groups examined. Plasma [Na+] and [Cl-] increased in response to both S and R. Increases in [Na+] and [Cl-] evoked by S but not R were prevented by DEX treatment. The results show that in the NIL, osmotic stimulation decreases AVP and OXY content, while it increases the CRF-41 content.
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PMID:Osmotic stimulation affects neurohypophysial corticotropin releasing factor-41 content: effect of dexamethasone. 234 90

The paraventricular nucleus (PVH) of the hypothalamus is a key region for the integration of the autonomic and neuroendocrine mechanisms. This integration becomes less reliable with age. Some critical functions, such as eating and drinking, body-temperature regulation, autonomic and endocrine responses which regulate the cardiovascular system seem to be particularly affected by the aging-related processes. In this paper, we analysed by means of immunocytochemistry the neurochemical organization of the magnocellular and parvocellular component of the PVH in old male rats. The main results concerning the neurohormones and the carrier proteins are the following: a significant decrease in the number of the oxytocin- (OXY) like immunoreactive neurons of the medial and lateral parvocellular nuclei; a decrease in the vasopressin- (VAS) like immunoreactive neurons of the medial and lateral parvocellular nuclei and also of the medial magnocellular nucleus; a decrease in the neurophysin- (NRP) like immunoreactive neurons of the lateral parvocellular nucleus. We also found a decrease in the mean area of magnocellular OXY- and VAS-like immunoreactive neurons, a decrease in the extension of the dendritic tree sampled in the medial part of the nucleus; a decrease in the number of varicosities along the neurons coming from the PVH, and in the density of axons in the median eminence and in the vagal complex. The NRP-like immunoreactive structures in the substantia gelatinosa of the spinal cord of old rats were also decreased in respect to younger adult animals. Among the neuropeptides investigated (corticotropin-releasing factor, leu-enkephalin, somatostatin, cholecystokinin and neurotensin) we found a decrease in the leu-enkephalin-like immunoreactive neurons of the dorsal and medial parvocellular nuclei. Our data support--from a morphological point of view--the existence of involution processes in the neurochemical organization of the PVH during aging.
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PMID:Influence of aging on the neurochemical organization of the rat paraventricular nucleus. 236 52

Previous immunocytochemical studies reported that when specific monoclonal antibody directed against vasopressin (VP) (VP-MAb) was injected in vivo above the rat hypothalamic nuclei, it penetrated and was specifically transported by VP-producing neurons. In this study, using the same methodological approach, the fate of monoclonal antibody directed against corticotropin-releasing factor (CRF) (CRF-MAb) injected in vivo above the paraventricular nucleus (PVN) of the rat brain was investigated by immunocytochemistry in male Zucker rats and adrenalectomized or colchicine-pretreated male Long-Evans rats. The simultaneous immunocytochemical localization of the injected CRF-MAb and endogenous peptides and enzyme synthesized by the neurons penetrated by the antibody, demonstrated that CRF-MAb was mainly detected in CRF neurons. But the CRF-MAb was also detected in VP, oxytocin, neuropeptide Y and tyrosine hydroxylase-producing neurons of the PVN. CRF-MAb was therefore localized in PVN neurons which synthesize CRF and in PVN neurons with physiological and morphological relationships with the CRF peptidergic system. Before obtaining biological effects of injected CRF-MAb, the results described here suggest that specific monoclonal antibodies provide a useful specific tool for elucidating the functional relationships between neuronal systems.
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PMID:Uptake of a monoclonal antibody to corticotropin-releasing factor (CRF) into rat hypothalamic neurons. 237 97

Several studies have reported coexistences of peptides in parvocellular neurons of the paraventricular nucleus (PVN). However, the coexistence of peptides in the magnocellular PVN is less clear. Controversy exists in particular about the coexistence of corticotropin-releasing factor (CRF) and oxytocin (OX). Although these peptides are present in distinct areas of the PVN, some overlap may exist. This study investigated a potential coexistence of OX and CRF in magno- and parvocellular PVN. The data demonstrate with clarity that neurons containing both the mRNA for OX and the peptide CRF are present in subpopulations of magnocellular and parvocellular neurons of the PVN.
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PMID:Coexistence of CRF peptide and oxytocin mRNA in the paraventricular nucleus. 238 78

The unlabeled antibody enzyme method has been applied on adjacent sections in order to investigate coexistence of oxytocin (OXY) and corticotropin-releasing factor (CRF) within individual neurons of the hypothalamic paraventricular nucleus of the colchicine-treated rat, sheep and hedgehog. Our results show that, although OXY and CRF immunoreactivities are both expressed by a number of cells in the rat and the sheep paraventricular nucleus, this is not the case for the hedgehog.
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PMID:The coexistence of oxytocin and corticotropin-releasing factor in the hypothalamus: an immunocytochemical study in the rat, sheep and hedgehog. 241 88


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