Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01185 (vasopressin)
 23,126 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We recently reported that ovine corticotropin releasing factor (CRF) infusion in conscious dogs elevated plasma vasopressin. The present study examines the vasopressin, adrenocorticotropic hormone (ACTH), and cortisol responses to CRF infusion (20 ng X kg-1 X min-1), to hypertonic saline infusion (NaCl 0.054 meq X kg-1 X min-1), and to simultaneous coinfusion of CRF and NaCl (CRF + NaCl) without (no-dex) or with (dex-treated) dexamethasone pretreatment in six conscious dogs (6-8 experiments/dog). CRF had no significant effect on plasma sodium or osmolality, blood pressure, or heart rate. NaCl increased plasma sodium from 146 +/- 1 to 151 +/- 1 meq/l and plasma osmolality from 298 +/- 3 to 305 +/- 3 mosmol/kg. Vasopressin increased significantly during CRF (2.1 +/- 0.5 to 4.8 +/- 1.1 pg/ml) and NaCl (1.9 +/- 0.3 to 5.0 +/- 0.8 pg/ml). Coinfusion of CRF and NaCl resulted in a response larger than the sum of the two infusions alone (3.0 +/- 1.6 to 31.4 +/- 18.5 pg/ml). The ACTH response to CRF (45 +/- 8 to 288 +/- 88 pg/ml) was not augmented by coinfusion with NaCl. DEX attenuated the vasopressin and ACTH responses to each infusion. We conclude that CRF-induced increases in vasopressin are augmented by a simultaneous osmotic stimulus. In addition, the plasma vasopressin responses to CRF and/or hypertonic saline infusion are inhibited by glucocorticoid pretreatment.
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PMID:Vasopressin responses to corticotropin releasing factor and hyperosmolality in conscious dogs. 302 13

Several lines of evidence have suggested that neurohypophysial vasopressin secretion is under the influence of glucocorticoid negative feedback. Studies in clinical and experimental adrenal insufficiency have suggested that the impaired water excretion accompanying that syndrome may be due to elevated vasopressin levels. Furthermore, both the impaired water excretion and elevated vasopressin levels observed in adrenal insufficiency may be normalized by glucocorticoid treatment. This topic remains controversial, with a considerable body of evidence suggesting that vasopressin is elevated during adrenal insufficiency not because of a loss of central steroid negative feedback but because of alterations in plasma volume osmolality (renal mechanisms). Vasopressin responses to a variety of stimuli (hemorrhage, hypoxia, hypertonic saline) in normal humans and animals appear to be attenuated or eliminated by pretreatment with glucocorticoids. However, the vasopressinergic system appears to be considerably less sensitive to negative feedback than the corticotropin-releasing factor-adrenocorticotropic hormone (ACTH) system. There is evidence that the locus for this inhibitory effect is both directly at the posterior pituitary and within the hypothalamus. It is unlikely that corticosteroid negative feedback closes a direct hypothalamo-neurohypophysial-adrenocortical feedback loop. Since neurohypophysial vasopressin is involved in the control of ACTH secretion, it is more likely that the modulation of neurohypophysial vasopressin by glucocorticoid is an integral part of the overall negative-feedback control of ACTH secretion. The physiological role of glucocorticoid inhibition of vasopressin secretion remains speculative.
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PMID:Glucocorticoid inhibition of neurohypophysial vasopressin secretion. 303 1

The quantitative autoradiographic deoxyglucose method was used to study the effects of acute adrenalectomy on local cerebral glucose utilization in conscious albino rats. Five hours following removal of the adrenal glands, glucose utilization was increased (4-55%) throughout the brain, particularly in the locus ceruleus, hypothalamic paraventricular nucleus, hippocampus, median eminence and anterior lobe of the pituitary gland. These structures are involved in the regulation of corticotropin-releasing factor, vasopressin, and adrenocorticotropic hormone. Treatment with dexamethasone (0.25 mg/kg i.m.) substantially reduced or prevented the stimulatory effects of adrenalectomy on cerebral glucose metabolism. These results demonstrate: (1) the existence of a negative feedback loop between the brain and adrenal glands in which corticosteroids exert an inhibitory action on glucose utilization of brain regions participating in adrenotropic regulation, and (2) a general inhibitory action of glucocorticoids on cerebral metabolism.
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PMID:Local cerebral glucose utilization is increased in acutely adrenalectomized rats. 337 57

Corticotropin-releasing factor (CRF) is thought to be an endogenous mediator of adrenocorticotropic hormone release following stress. We examined if CRF initiates further biological actions that are observed in response to stressful events. Male beagle dogs (10-12 kg) were fitted with a chronic intracerebroventricular cannula, intra-arterial and intravenous catheters, as well as a gastric fistula. Synthetic human CRF was microinjected into the third cerebral ventricle in conscious animals. CRF (0.1-1.0 nmol/kg) significantly (P less than 0.01) increased plasma concentrations of epinephrine, norepinephrine, glucagon, and glucose and elevated mean arterial pressure and heart rate. Pretreatment of the animals with the ganglionic blocking agent chlorisondamine completely abolished the increases in plasma catecholamine and glucose concentrations as well as the elevations in blood pressure and heart rate. CRF significantly (P less than 0.01) inhibited gastric acid secretion, but not plasma gastrin concentrations stimulated by an 8% liquid peptone meal. The gastric inhibitory action of CRF was completely prevented by chlorisondamine and, in part, by naloxone and a vasopressin antagonist. In contrast, bilateral truncal vagotomy did not affect the gastric inhibitory action of CRF. The results of this study indicate that CRF acts within the central nervous system to increase plasma glucose and glucagon concentrations, mean arterial pressure, and heart rate by activation of the autonomic nervous system. CRF inhibits meal-stimulated gastric acid secretion by activation of the sympathetic nervous system and, in part, by opiate and vasopressin-dependent pathways and not by inhibition of gastrin release.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:CRF initiates biological actions within the brain that are observed in response to stress. 354 74

Properties of adenyl cyclase of normal adrenals and of a corticosterone-producing adrenal cancer of the rat have been compared. Enzyme activity was found in all particulate fractions of both tissues. The cyclase of the tumor as well as of the adrenals was stimulated by adrenocorticotropic hormone (ACTH) over similar concentration ranges. Unexpectedly, the tumor enzyme was also stimulated by epinephrine, norepinephrine, and thyroid-stimulating hormone (TSH). These hormones produced a dose-related effect over a concentration span that was comparable with that for ACTH. The tumor cyclase was not responsive to angiotensin Il, vasopressin, glucagon, insulin, growth hormone, parathyroid hormone, and thyrocalcitonin. ACTH was the only hormonal preparation that stimulated normal adrenal cyclase. These findings are compatible either with the possibility that the adenyl cyclase receptor of the tumor has undergone structural alteration with a consequent loss of specificity for ACTH or with the possibility that the tumor possesses several cyclase regulatory receptors.
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PMID:Abnormal hormone responses of an adrenocortical cancer adenyl cyclase. 432 11

Protein carboxymethylase, an enzyme capable of methylating proteins and polypeptides, was purified from bovine pituitary. The anterior pituitary hormones, luteinizing hormone, follicle-stimulating hormone, adrenocorticotropic hormone, growth hormone, thyroid-stimulating hormone, and prolactin, were found to be substrates for this enzyme. The posterior pituitary hormones, oxytocin and vasopressin, did not serve as substrates. With luteinizing hormone as the substrate, protein carboxymethylase had a pH optimum near pH 5.5. A limiting K(m) of 1.47 muM for S-adenosyl-L-methionine was obtained with luteinizing hormone as the methyl acceptor. Possible roles of this enzyme in the posterior and anterior pituitary are discussed.
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PMID:Characterization and substrate specificity of a protein carboxymethylase in the pituitary gland. 436 60

A 29-year-old woman with evidence of a craniopharyngioma and documented panhypopituitarism is described. Clinical and laboratory evaluation revealed deficiencies of follicle-stimulating hormone, luteinizing hormone, thyroid-stimulating hormone, growth hormone, prolactin, adrenocorticotropic hormone and antidiuretic hormone. Prompt release of several pituitary hormones was noticed after administration of the hypothalamic releasing hormones FSH/LH-RF and thyrotropin-releasing hormone, whereas insulin-induced hypoglycemia, levodopa, chlorpromazine and clomiphene citrate, all of which act at the level of the hypothalamus, did not alter basal pituitary secretion. The patient's height of 60 inches, despite panhypopituitarism, and the interpretation of the above data are discussed in the light of current concepts regarding the dynamics of the hypothalamic-hypophyseal system.
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PMID:Survival and growth in a woman with untreated hypothalamic panhypopituitarism of 21 years' duration. 437 Apr 18

To date about thirty peptides--low-molecular-weight, single-chain amino acid compounds--are known to be distributed widely in the central nervous system within selective neuron pathways. These findings, combined with a large body of neuropharmacological, behavioral, and electrophysiological data, open new horizons in neurobiology, force a reexamination of old and accepted hypotheses, and hold important implications for the clinician. There is evidence that substance P and the opioid peptides play a major role in the pain pathway, particularly at the level of the spinal cord. Available evidence also implicates vasoactive intestinal polypeptide in the control of cerebral circulation, cholecystokinin in the regulation of appetite, and vasopressin and adrenocorticotropic hormone in memory. Many questions, however, remain. For most peptides there is little information on mechanisms of biosynthesis, release, interaction with receptors, and termination of biological effect. Another important question is the interaction of peptides with other neurotransmitters. The evidence that both "classic" neurotransmitters and peptides can be found in the same neuronal necessitates reformulation of Dale's "one neuron, one neurotransmitter" hypothesis. It may be that a single cell, while containing different classes of neurotransmitter, will contain only one member of any particular class. It is not too early to speculate on the role of the numerous and diverse peptides in neuronal tissue and on the implications of peptide abnormalities in a variety of neurological diseases. The answers to these and other questions pose a fascinating challenge to neurobiologist and clinician alike.
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PMID:Neuroendocrinology and brain peptides. 616 92

Initially the hypothalamic factor responsible for the release of corticotropin (CRF), was thought to be a simple peptide. More recent work has led to the conclusion that CRF is a multifactorial complex. In 1979 we proposed that vasopressin, much disputed as a CRF candidate, was a major constituent of the complex, interacting with a potentiating the CRF activity of the other component(s). The recent characterization of a 41 residue ovine hypothalamic peptide capable of releasing adrenocorticotropic hormone (ACTH) in a dose-related manner has allowed us to compare its CRF bioactivity with that of vasopressin and simple extracts of the hypothalamus, and to investigate any interaction it may have with vasopressin and other hypothalamic factors in the release of ACTH. We report here that the new CRF is more potent than vasopressin in releasing ACTH. When given simultaneously with vasopressin a fourfold potentiation of CRF activity with steep dose-response characteristics were observed. It also potentiated vasopressin-free hypothalamic extracts, suggesting that a new CRF does not account for all the nonvasopressin portion of the CRF complex.
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PMID:Corticotropin releasing activity of the new CRF is potentiated several times by vasopressin. 628 93

Most of the experimental evidence for a role of arginine-vasopressin (AVP) in adrenocorticotropic hormone (ACTH) release comes from in vitro studies. The multimolecular nature of the hypothalamic factor responsible for corticotropin (CRF) release has long been recognized, but the importance of AVP as a cofactor is controversial. The recently characterized 41-residue peptide fulfills the criteria for a physiological role in ACTH release and it is potentiated in vitro by AVP. In vivo, AVP is able to stimulate ACTH secretion, and Brattleboro rats, deficient in AVP, show a reduced activity of the hypothalamo-hypophysial-adrenocortical system (HHCS) (see ref. 13 for references). Direct evidence for involvement of AVP in the physiological release of ACTH is, however, still lacking. The recent development of AVP receptor antagonists provides the opportunity to test this hypothesis directly. I report here that pretreatment by 1-deaminopenicillamine, 2-(O-methyl)tyrosine arginine-vasopressin (dPTyr(Me)AVP), a potent antagonist of the vasopressor, behavioural and ACTH-releasing properties of AVP, does not modify the ACTH and corticosterone secretion induced by exposure to a novel environment, but totally inhibits the increase of ACTH and corticosterone levels induced by AVP. The results do not support the hypothesis for a physiological involvement of AVP in ACTH release.
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PMID:The vasopressin receptor antagonist dPTyr (Me) AVP does not prevent stress-induced ACTH and corticosterone release. 630 Jun 79


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