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)

The effects of rat CRF, arginine vasopressin (VP), oxytocin (OXY), and isoproterenol (ISO) on the biosynthesis and release of pro-ACTH/endorphin-derived peptides by monolayer cultures of rat anterior pituitary cells in complete serum-free medium (CSFM) were studied. When cells were exposed to hormone for 3 h, CRF, VP, OXY, and ISO were each able to stimulate secretion of immunoactive hormone into culture medium. To determine the effects of chronic secretagogue exposure on corticotrope function, cultures were exposed to hormone for 14 days, and total hormone production was measured by immunoassay (cumulative hormone secreted plus cell hormone content). In the absence of CRF, total hormone production increased 3.6 +/- 0.2-fold (mean +/- SEM) over the period from 2-14 days; chronic CRF treatment brought about a 7.9 +/- 0.7-fold increase in total hormone production over the same period (P less than 0.0025) or a 2.2-fold increase over control cells. Total hormone production was not affected by chronic treatment with VP (100 nM), OXY (100 nM), or ISO (100 nM); the response of the cells to chronic CRF treatment was unaltered by chronic inclusion of VP, OXY, or ISO. To examine the chronic effects of secretagogues more directly, anterior pituitary cells were grown in control CSFM or in CSFM containing CRF or VP for 7 days and then incubated in medium containing radiolabeled amino acid for 15 min. The newly synthesized pro-ACTH/endorphin was quantified by immunoprecipitation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Cells grown in CSFM containing CRF synthesized 1.9 times more labeled pro-ACTH/endorphin that cells grown in control CSFM or in CSFM containing VP. Chronic exposure of anterior pituitary cultures to 8-bromo-cAMP stimulated both synthesis and release of pro-ACTH/endorphin-derived peptides, suggesting that a secretagogue capable of producing a sustained elevation in intracellular cAMP levels will stimulate prohormone synthesis.
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PMID:Effect of chronic secretagogue exposure on pro-adrenocorticotropin/endorphin production and secretion in primary cultures of rat anterior pituitary. 349 70

CRF-containing parvocellular axons in the external zone of the rat median eminence were classified as vasopressin-containing (CRF+/AVP+) and vasopressin-deficient (CRF+/AVP-) subpopulations based on post-embedding electron microscopic immunocytochemical staining of serial ultrathin sections for CRF, AVP and the other peptides derived from the AVP precursor: AVP-associated neurophysin (NP-AVP) and the C-terminal glycopeptide (GP). In normal animals, the CRF+/AVP+ and CRF+/AVP- subpopulations were approximately equal in terms of detectable axonal swellings. Three to 14 days after adrenalectomy (ADX), the CRF+/AVP+ and CRF+/AVP- subpopulations represented about 95% and 5%, respectively, of total CRF+ swellings. This change was due to a 90% decrease in the absolute number of detectable CRF+/AVP- swellings after ADX, whereas the absolute number of detectable CRF+/AVP+ swellings rose by less than 20%. These changes were completely blocked by administering the glucocorticoid agonist dexamethasone throughout the period after ADX. The results suggest that the CRF+/AVP+ and CRF+/AVP- subpopulations of neurosecretory axons in the external zone of the median eminence respond differently to ADX, indicating that they are independently regulated by glucocorticoids.
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PMID:Vasopressin-containing and vasopressin-deficient subpopulations of corticotropin-releasing factor axons are differentially affected by adrenalectomy. 349 95

The aim of the study was to investigate CRF- and neurophysin-immunoreactive neurocytes in hypothalamo-pituitary system of the hamster. CRF-immunoreactive nerve fibers were observed mainly in the outer layer of the median eminence and pituitary stalk and also in the neurohypophysis. On the contrary, neither intermediate lobe nor anterior pituitary contained CRF-immunoassayable substance. The pattern of distribution of neurophysin-immunoreactive fibres was different from CRF-immunoreactive fibres as far as a median eminence, pituitary stalk and neurohypophysis are concerned. Between the tannocytes of the III ventricle and nervous fibres forming the internal layer of the median eminence a CRF- and neurophysin-immunoreactive perikaryons of neurocytes were found. Results of the study suggest regulatory function of CRF-immunoreactive neurons of the hamster hypothalamo-pituitary system in controlling of ACTH secretion. Moreover, the distribution of CRF-immunoreactive substances in hamster hypothalamo-pituitary system shows some peculiarities if compared with other rodents.
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PMID:Studies on hypothalamo-pituitary corticoliberin system. II. Corticotropin-releasing factor (CRF) and neurophysin (NP) immunoreactive neurocytes in the hamster. 350 64

A tabular synopsis is presented for articles concerned with the effects of peptides on the central nervous system that appeared in the journal Peptides from 1980-1985. A table arranged alphabetically by peptide and one arranged by effects, both listing routes of injection, species, direction of change, and qualifying notes, provides easy cross-referencing of peptides and their effects. Over 80 peptides and over 135 effects are listed. The list of peptides includes, but is not limited to: ACTH, angiotensin, bombesin, bradykinin, calcitonin, casomorphin, CCK, ceruletide, CGRP, CRF, dermorphin, DSIP, dynorphin, endorphins, enkephalins, GRF, gastrin, LHRH, litorin, metkephamid, MIF-l, motilin, MSH, NPY, NT, oxytocin, ranatensin, sauvagine, substances P and K, somatostatin, TRH, VIP, vasopressin, and vasotocin. The list of effects includes, but is not limited to: aggression, alcohol, analgesia, attention, avoidance, behavior, cardiovascular regulation, catalepsy, conditioned behavior, convulsions, dopamine binding and metabolism, discrimination, drinking, EEG, exploration, feeding, fever, gastric secretion, GI motility, grooming, learning, locomotor behavior, mating, memory, neuronal activity, open field, operant behavior, rearing, respiration, satiety, scratching, seizure, sleep, stereotypy, temperature, thermoregulation and tolerance.
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PMID:Central nervous system effects of peptides, 1980-1985: a cross-listing of peptides and their central actions from the first six years of the journal Peptides. 353 8

Levels of immunoreactive (IR) oxytocin (OT)-associated or estrogen-stimulated neurophysin (ESN) and vasopressin-associated or nicotine-stimulated neurophysin (NSN) were measured in plasma of patients with chronic renal failure before and after hemodialysis (HD) and intermittent peritoneal dialysis (IPD), and during continuous ambulatory peritoneal dialysis (CAPD). ESN-IR in 17 patients before HD was 24.4 +/- 2.7 ng/ml (mean +/- SEM) and increased after HD to 33.2 +/- 4.1 ng/ml (P less than 0.001). ESN-IR in 17 patients with CAPD was 15.2 +/- 3.4 ng/ml, significantly lower than in patients undergoing HD, P less than 0.001. In patients receiving IPD (n = 6), ESN was 11.6 +/- 3.7 ng/ml and did not change significantly after IPD. Levels of ESN in patients with renal failure were increased compared with levels in normal individuals, 1.0 +/- 0.1 ng/ml. Levels of ESN were not correlated with laboratory parameters that may be abnormal in renal failure. NSN levels in 16 of 17 patients undergoing HD were 3.2 +/- 0.34 ng/ml and in 14 of 17 patients with CAPD were 2.9 +/- 0.4 ng/ml, respectively. ESN before HD (r = 0.63, P less than 0.01), after HD (r = 0.85, P less than 0.001), and in patients with CAPD (r = 0.83, P less than 0.001) and IPD (r = 0.81, P less than 0.05) correlated significantly with an OT-like peptide previously found to be increased in renal failure.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:High-performance liquid chromatographic characterization of neurophysins in chronic renal failure. 365 23

The presence of cholecystokinin and gastrin has been reported in the hypothalamohypophyseal system. These peptides present a peculiar distribution in the hypothalamic nuclei, the median eminence, and the neurohypophysis. CCK and gastrin have close relationships with other peptides like oxytocin, CRF, vasopressin, and the enkephalins; these relationships vary in different projecting areas and in different types of hypothalamic neurons. The functional role of G-CCK in neurosecretion seems to be linked to the role of these closely associated peptides and certainly deserves further investigation.
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PMID:Co-existence of cholecystokinin- or gastrin-like peptides with other peptides in the hypophysis and the hypothalamus. 387 5

Antisera raised against the synthetic CRF allowed us to visualize by immunohistochemistry, the hypothalamic neurons which contain this peptide or a related substance. The perikarya are distributed in the paraventricular nucleus. They likely represent the origin of the numerous nerve terminals localized around the vessels of the hypophyseal portal plexus. In guinea-pig and rat after adrenalectomy and in the intact lerot, the pericapillary terminals reacting for CRF, also contain a substance related to bovine neurophysin. Moreover, in the guinea-pig, adrenalectomy appeared to induce a CRF-immunostaining in the LH-RH terminals.
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PMID:[Immunohistochemical localization of CRF in the hypothalamus of 3 rodents]. 613 87

A new peptidergic paraventriculo-infundibular system has been revealed using anti-corticoliberin (CRF) antibodies. The localization of its perikarya in the paraventricular nuclei as well as the distribution of its fibres and perivascular nerve-endings within the median eminence are different from those of other systems stained with antibodies directed against gonadoliberin, somatostatin, vasopressin or oxytocin.
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PMID:[Corticoliberin neurons in the rat brain]. 621 70

The present paper reports new findings concerning interaction of [3H]-Arginine-vasopressin with putative receptors in rat anterior pituitary gland. It shows the presence of a single type of receptor sites, with a limited binding capacity and a dissociation constant of nearly 1nM. The parent neurohormone oxytocin revealed weak affinity as compared with vasopressin [Ki = 100nM and Ki = 1nM, respectively]. None of the various peptides tested and, especially corticotropin-releasing factor CRF, competed for binding. Receptor characteristics appeared to be unaffected by lack of circulating vasopressin in Brattleboro rats presenting complete deficiency in synthesis of that peptide.
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PMID:Characterization of specific receptors for vasopressin in the pituitary gland. 631 81

We have investigated the effects of synthetic oxytocin and vasopressin on corticotropin release induced by the 41-residue ovine corticotropin-releasing factor (oCRF) in vitro. Segments of the anterior pituitary glands obtained from male and female Wistar or from female hetero- and homozygous Brattleboro rats were used. Ovine CRF (0.1-2.5 nmol/l) stimulated corticotropin release by pituitaries of Wistar rats and this effect was augmented two- to threefold in the presence of arginine vasopressin (0.09-0.9 mIU/ml) or oxytocin (0.9-90 mIU/ml). A similar phenomenon was demonstrated in Brattleboro rats. These data favor the hypothesis that oxytocin might have a physiological role in the regulation of pituitary-adrenocortical function in homozygous Brattleboro rats which lack vasopressin.
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PMID:Oxytocin as well as vasopressin potentiate ovine CRF in vitro. 631 91


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