Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01189 (beta-endorphin)
 21,003 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Oxytocin, a hypothalamo-neurohypophyseal neuropeptide was found to attenuate the development of tolerance to the analgesic action of morphine, heroin, beta-endorphin or D-Pro2-Met5-enkephalinamide. The effect of oxytocin on morphine tolerance was prevented by N alpha-acetyl-(2-0-methyltyrosine)-oxytocin or penicillamine1-(2-0-methyltyrosine)-lysine8-vasopressin, which are antagonists of oxytocin receptors. Oxytocin dose-dependently attenuated various signs of precipitated morphine withdrawal (e.g., stereotyped jumpings, hypothermia, body weight loss). The neuropeptide diminished intravenous self-administration of heroin in heroin-tolerant rats. It is concluded that brain oxytocin interferes with adaptive components of experimental drug addiction.
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PMID:Hypothalamo-neurohypophyseal neuropeptides and experimental drug addiction. 284 8

The direct effect of vasopressin on adrenal steroidogenesis and its effect on angiotensin II- and adrenocorticotropic hormone (ACTH)-stimulated steroidogenesis was evaluated by using an isolated perfused canine adrenal gland preparation. Infusions of vasopressin alone (50, 100, or 250 pg/ml perfusate) had no significant effect on the secretion of either aldosterone or cortisol. Infusions of vasopressin at 75 or 250 pg/ml perfusate during stimulation of steroidogenesis by angiotensin II or by ACTH did not cause a consistent increase in aldosterone secretion. In contrast, infusion of 250 but not 75 pg vasopressin/ml perfusate caused a consistent enhancement of ACTH-stimulated cortisol secretion. The infusion of a vasopressin V1-receptor agonist, but not of either a vasopressin V2-receptor agonist or oxytocin, also caused a significant enhancement of ACTH-stimulated cortisol secretion. These results suggest that the sensitivity of fasciculata cells to vasopressin is greater than that of glomerulosa cells. Finally, levels of vasopressin reported to occur in plasma during severe hemorrhage appear to be capable of enhancing cortisol secretion by a direct action on the adrenal gland via a V1-receptor mechanism.
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PMID:Effect of vasopressin on adrenal steroidogenesis. 284 63

Following two weeks of cerebroventricular administration of arginine-vasopressin (AVP) by Accurel implants, two types of binding sites for this peptide were immunocytochemically visualized in blood vessels in the brain of Brattleboro (di/di) rats: (1) endothelial cells of capillaries were stained with the highest density in hippocampus, striatum, and locus coeruleus (LC), whereas only few such stained cells were present in the septum and cerebral cortex. (2) Bound AVP was also present on endothelial cells and pericyte-like cells in larger blood vessels in striatum and the LC. Both types of vasopressin binding site staining on blood vessels were dose-dependent and could be further enhanced by additional in vitro preincubation of the fixed sections with AVP. This staining was not present in rats implanted with either oxytocin or alpha-melanocyte-stimulating hormone.
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PMID:Immunocytochemically stained vasopressin binding sites on blood vessels in the rat brain. 285 93

The purpose of this study was to compare the control of adrenocorticotropin (ACTH) and corticosterone secretion in homozygous Brattleboro rats with their syngeneic controls, Long-Evans rats, and with rats of the Wistar strain. Plasma concentrations of ACTH and corticosterone were measured by radioimmunoassay in trunk blood, and corticotropin-releasing factor 41 (CRF-41), arginine vasopressin (AVP), and oxytocin were assayed in hypophysial portal vessel blood. Portal plasma was extracted with methanol for CRF-41 determination, and four different antisera and several different high-performance liquid chromatography (HPLC) systems were used to investigate AVP release. The peripheral plasma concentrations of ACTH and corticosterone were significantly higher in Long-Evans and homozygous Brattleboro than in Wistar rats. This difference was due, at least in part, to an approximately twofold greater release of CRF-41 into hypophysial portal blood of the Long-Evans and Brattleboro compared with Wistar rats. There was no significant difference between the strains in the output of oxytocin into portal blood. While no AVP could be detected in the neural lobe of homozygous Brattleboro rats, a small amount of AVP-like immunoreactivity was detected in unextracted hypophysial portal blood from homozygous Brattleboro rats. However, this AVP-like immunoreactivity was clearly distinct from authentic AVP in several HPLC systems, had no antidiuretic activity, and on gel filtration had a relative molecular mass greater than 5 kD. In contrast, the AVP-like immunoreactivity in hypophysial portal blood from Long-Evans rats co-eluted with authentic AVP in all HPLC systems tested.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Comparison of adrenocorticotropin control in Brattleboro, Long-Evans, and Wistar rats. Measurement of corticotropin-releasing factor, arginine vasopressin, and oxytocin in hypophysial portal blood. 285 6

The rat neurohypophysis contains both opioid receptors and substantial amounts of endogenous opioid peptides. Inhibitory influences of opioids on the secretion of both oxytocin and vasopressin have been described. We have examined the effects of a range of opioid agonists and antagonists with differing relative selectivities towards opioid receptor subclasses on the secretion of oxytocin and vasopressin from the isolated neurohypophysis. Oxytocin and vasopressin release evoked by brief periods of electrical stimulation in control experiments was compared to evoked release in the presence of test compounds. Oxytocin release was depressed approximately 25% by the delta-agonist (D-Ala2, D-Leu5)-enkephalin but not affected by putative kappa-agonists or by beta-endorphin. The use of opioid antagonists revealed a strong inhibition of oxytocin secretion by endogenous opioids released during electrical stimulation. Naloxone, relatively mu-selective, enhanced oxytocin secretion by up to 90% with a half-maximal effect at approximately 10(-6) M. MR2266, a relatively kappa-selective antagonist also enhanced oxytocin secretion but displayed agonist-like activity at high concentrations. ICI 154129, a delta-selective antagonist, was without effect on oxytocin secretion. Vasopressin release was unaffected by any of the agonists tested and not potentiated by antagonists at a range of stimulation frequencies. The data do not support the suggestion of an inhibitory endogenous opioid influence over vasopressin secretion within the neurohypophysis but indicate that an endogenous opioid peptide, possibly acting via mu- or kappa rather than delta-receptors, strongly suppresses the secretion of oxytocin.
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PMID:Effects of opioid agonists and antagonists on oxytocin and vasopressin release in vitro. 286 49

As a first step toward assessing the status of brain neuropeptide systems that may be involved in Alzheimer's disease (AD), the cerebrospinal fluid (CSF) concentrations of the neuropeptides arginine vasopressin, somatostatin, oxytocin, and beta-endorphin were measured in patients with AD, normal elderly subjects, and normal young subjects. The plasma arginine vasopressin level was also measured in the three groups. The CSF arginine vasopressin level was significantly lower in patients with AD than in either elderly or young normal subjects, but oxytocin and beta-endorphin levels did not differ between groups. The CSF osmolarity also did not differ between groups. The plasma arginine vasopressin level did not significantly differ between groups, but high plasma arginine vasopressin values were absent in the patients with AD. The CSF somatostatin level was significantly lower in patients with AD than in normal elderly persons, but it did not differ in young normal subjects. These results suggest that central vasopressinergic activity may be decreased in AD and confirm reports of low CSF somatostatin levels in AD.
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PMID:Cerebrospinal fluid vasopressin, oxytocin, somatostatin, and beta-endorphin in Alzheimer's disease. 286 44

The distribution of arginine-vasopressin (AVP)-, oxytocin-, beta-endorphin (beta-EP)- and dynorphin-immunoreactive cells was examined by peroxidase-antiperoxidase (PAP) immunocytochemistry in the ovaries of Brattleboro and Long-Evans (LE) rats. The ovarian distribution of the peptide-immunoreactivity is indistinguishable between the two strains. AVP- and beta-EP-immunoreactivity is co-localized in the majority of luteal cells, and in some cells scattered in the interstitial tissue. Of the AVP/beta-EP-positive cells, 1-2% also contained immunoreactive (ir)-dynorphin. Some cells in the interstitium contained only ir-AVP (approximately 50%) or only ir-dynorphin (approximately 5%); in the corpora lutea, however, no luteal cells appeared to contain only one peptide. AVP-immunoreactivity is also present in theca cells surrounding secondary and large, antral follicles; ir-oxytocin was not observed in any ovarian cell type in the rat. These data suggest that most luteal, and some interstitial, cells in the ovary have the capacity to produce and store up to three different neuropeptides.
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PMID:Co-expression of vasopressin with beta-endorphin and dynorphin in individual cells from the ovaries of Brattleboro and Long-Evans rats: immunocytochemical studies. 287 49

The present study investigated the possible effect of somatostatin and oxytocin on the basal and stress-induced rise of beta-endorphin (beta-END), beta-lipotrophin (beta-LPH) and cortisol in the human. For this purpose somatostatin (4.1 micrograms/min for 120 min or oxytocin (0.4 micrograms/min for 120 min) was infused into two different groups of seven healthy subjects; 30 min after the start of the infusion, placebo or insulin (0.1 IU/kg body weight, B.W.) was injected on two different days. In a third experimental step, an insulin tolerance test was performed during saline infusion to evaluate stress-related effects on the different hormonal secretions under basal conditions. Plasma levels of beta-END, beta-LPH and cortisol were measured by radioimmunoassay. Extraction and chromatographic procedures preceded the assay for beta-END and beta-LPH. Neither somatostatin nor oxytocin significantly modified basal plasma levels of beta-END, beta-LPH and cortisol. However these treatments blunted the rise of the three hormones seen at 45 and 60 min during insulin-induced hypoglycaemia (P less than 0.01). These results indicate that somatostatin and oxytocin may influence the beta-END, beta-LPH and cortisol increase induced by stress in humans, without affecting their basal secretion.
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PMID:Somatostatin and oxytocin infusion inhibits the rise of plasma beta-endorphin, beta-lipotrophin and cortisol induced by insulin hypoglycaemia. 287 46

The anteroventral periventricular nucleus (AVPv), which lies in the periventricular zone of the preoptic region, is critical for normal phasic gonadotropin secretion since lesions of this nucleus abolish the progesterone-induced surge of luteinizing hormone secretion from the anterior pituitary, block ovulation, and induce persistent vaginal estrus in female rats. However, very little is known about the neurotransmitter-specific pathways associated with this nucleus. In the present study we evaluated the distribution of biochemically specific cells and fibers within the AVPv and adjacent regions by using an indirect immunohistochemical method with antisera to serotonin (5-HT), dopamine beta-hydroxylase (DBH), tyrosine hydroxylase (TH), neuropeptide Y (NPY), cholecystokinin-8 (CCK), vasoactive intestinal polypeptide (VIP), substance P (SP), neurotensin (NT), corticotropin-releasing factor (CRF), luteotropin-releasing hormone (LRH), somatostatin (SS), thyrotropin-releasing hormone (TRH), oxytocin (OXY), vasopressin (VAS), adrenocorticotropic hormone (ACTH1-24), alpha-melanocyte-stimulating hormone (alpha-MSH), leucine-enkephalin (L-ENK), and calcitonin gene-related peptide (CGRP). Our findings indicate that both cells and fibers containing these putative neurotransmitters are differentially distributed in and around the AVPv in accordance with the cytoarchitectonic organization of this part of the preoptic region. The AVPv itself appears to receive strong inputs from SP-, VAS-, CCK-, and SS-containing pathways, whereas the highest densities of L-ENK-, NT-, 5-HT-, NPY-, and DBH-immunoreactive fibers were found in the cell-sparse zone just lateral to the AVPv. The suprachiasmatic preoptic nucleus (PSCh), a small group of cells located ventral to the AVPv just dorsal to the optic chiasm, contained high densities of alpha-MSH- and ACTH-immunoreactive fibers, as well as substantial numbers of fibers containing catecholamines or NPY. In contrast, a dense plexus of VAS-stained fibers was distributed fairly evenly throughout the AVPv and PSCh. Numerous L-ENK-immunoreactive cell bodies, and moderate numbers of CCK-, NT-, and CRF-stained cell bodies were found in the AVPv. The PSCh contained many TH-stained cells (presumably dopaminergic), in addition to a moderate number of CCK-containing cell bodies, while a high density of NT- and CRF-stained cells were found in the cell-sparse zone lateral to the AVPv, in addition to several CCK-, SP-, VIP-, and TH-containing cells.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:The distribution of neurotransmitter-specific cells and fibers in the anteroventral periventricular nucleus: implications for the control of gonadotropin secretion in the rat. 288 Jun 34

The subcommissural organ (SCO) of the snake Natrix maura was studied by use of the immunoperoxidase procedure. Primary antisera against bovine neurophysins (Nps I + II, OXY-Np), oxytocin (OXY), mesotocin (MST), arginine-vasotocin (AVT), somatostatin (SOM), beta-endorphin (END) and bovine Reissner's fiber were used. A conventional ultrastructural study, with special emphasis on the nerve fibers present in the SCO, was also performed. Nerve fibers containing immunoreactive OXY-Np and MST were seen to reach the SCO. The staining of adjacent sections with the anti-Reissner's fiber serum showed that the OXY-Np- and MST-immunoreactive fibers were distributed among the cell bodies and processes of the ependymal secretory cells. No fibers containing immunoreactive OXY, AVT, SOM or END were found in the SCO. The ultrastructural analysis revealed in the SCO the presence of nerve fibers filled with electron-dense granules, 170-210 nm in diameter. Although a direct apposition between these fibers and the SCO cells was frequently seen, no synaptic differentiations were identified. Structures identical to the Herring bodies (found in the neurohypophysis) were seen in the SCO.
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PMID:Immunocytochemical and ultrastructural evidence for a neurophysinergic innervation of the subcommissural organ of the snake Natrix maura. 288 36


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