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)

The prolactin (PRL)-releasing activity of porcine stalk median eminence (pSME) was characterized by an in vivo bioassay and concomitant radioi-munoassay of plasma PRL and thyrotropin (TSH) levels. Methanol extracts of pSME stimulated PRL release in 3-day estrogen-primed rats when administered by the intracarotid route in doses ranging from 0.1 to 2.0 pSME equivalents. Synthetic thyrotropin-releasing hormone (TRH) stimulated the release of PRL and TSH in the dose range of 10 to 300 ng. PRL release was greater in response to a maximally effective dose of pSME than the release elicited by a maximal dose of TRH, and pSME administered together with a greater than mazimally effective dose of TRH caused additional PRL but not TSH secretion. Lysine vasopressin and prostaglandin E1 and E2 stimulated PRL release only at doses several orders of magnitude greater than the dose present in pSME. Somatostatin inhibited the release of TSH but not that of PRL whether the stimulus employed was pSME or TRH. The effective inhibitory dose of somatostatin was also significantly greater than the reported hypothalamic content. When pSME was subjected to incubation with plasma, a treatment reported to inactivate TRH, TSH-releasing activity was destroyed to a greater extent than was PRL-releasing activity. When pSME was adsorbed onto charcoal, the supernatant solution was devoid of TRH, as determined by complete removal of a [3H]TRH marker, yet substantial PRL-releasing activity was retained. TSH-releasing activity eluted from the charcoal with methanol was considerably greater than that expected on the basis of the recovery of [3H]TRH, suggesting the presence in the crude extract of a TSH-release inhibitor or of a TSH-releasing factor other than TRH. Based on the above evidence, we conclude that crude pSME contains PRL-releasing substance(s) distinct from the tripeptide TRH.
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PMID:Dissociation of prolactin-releasing activity from thyrotropin-releasing hormone in porcine stalk median eminence. 81 52

A 25-year-old woman with severe diabetes mellitus since the age of 7 developed anterior pituitary insufficiency after pregnancy toxaemia with hypofunction of the thyroid, ovaries and adrenal cortex. Following the development of Sheehan's syndrome, her insulin requirment decreased dramatically. I.v. administration of TRH, LRH and vasopressin induced nearly normal pituitary response levels of TSH, LH and plasma cortisol, indicating a hypothalamic damage as the primary aetiological factor.
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PMID:Sheehan's syndrome of hypothalamic origin in a woman with juvenile diabetes mellitus. 93 82

A sensitive and specific double antibody radioimmunoassay has been developed capable of measuring LH-RH in extracted human plasma. Thyrotropin releasing hormone, lysine vasopressin and most of LH-RH analogues did not appear to affect the assay. Hypothalamic extract and some of the LH-RH analogues produced displacement curves which were parallel to that obtained with the synthetic LH-RH. Sensitivity of the radioimmunoassay was about 3 pg per assay tube. The coefficient of variation of intraassay was 6.4%, while that of interassay was 9.6%. Exogenous LH-RH could be quantitatively extracted by acidic ethanol when varying amounts of synthetic LH-RH were added to plasma. Immunoreactivity of LH-RH was preserved in plasma until 2 hr in the cold and gradually reduced thereafter. The plasma levels in LH-RH were 20 pg/ml or less in normal adults and not detectable in children. The aged males over 60 yr and postmenopausal women showed a tendency to have higher levels of plasma LH-RH. Plasma LH-RH level was significantly higher in midcycle than in follicular and luteal stages. The disappearance rate of LH-RH from the circulation after intravenous injection could be represented as half times of 4-6 min. Between 0.2-0.4% of the injected dose was excreted into urine within 1 hr. These results indicate that the determination of LH-RH might be a useful tool for elucidating hypothalamic-pituitary-gonad interactions.
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PMID:Radioimmunoassay for luteinizing hormone releasing hormone in plasma. 110 Mar 64

Two hundred and forty-one cases of isolated ACTH deficiency have been reported in Japan since 1969. Pituitary hormone responsiveness to stimulation tests before and after hydrocortisone supplementation was investigated in these cases. Plasma ACTH level showed no or little change in response to lysine vasopressin, metyrapone, CRF or insulin-induced hypoglycemia in 97.3-100% of the cases. Serum GH level changed little or not at all in response to GRF, insulin-induced hypoglycemia, glucagon, 1-dopa and arginine in 26.9, 29.3, 40.0, 50.0 and 56.1%, respectively. Serum TSH and prolactin (PRL) levels showed hyperresponse to TRH in 34.7 and 35.6%, respectively. After hydrocortisone therapy, GH secretion was more responsive than before therapy in 78.9% of the cases. After supplementation, TSH level was less responsive to TRH stimulation than before therapy in 59.3% of the cases. After hydrocortisone supplementation, TSH response to TRH decreased in 75% of ACTH-deficient patients without primary hypothyroidism but did not decrease in more than half of those with primary hypothyroidism. TSH response to TRH decreased after supplementation in 76.5% of the patients with TSH hyperresponsiveness before therapy, and increased after therapy in 66.7% of those with normal TSH responses before therapy. After supplementation, PRL response to TRH was less than that before therapy in 43.5% of ACTH--deficient patients, and greater than that before therapy in 30.4%. PRL response to TRH decreased after therapy in 66.7% of the patients with PRL hyperresponsiveness before therapy, and increased in 63.6% of those with normal PRL response before therapy. Primary hypothyroidism and Hashimoto's thyroiditis were complicated in 21.6 and 11.6%, respectively, of the 241 patients with isolated ACTH deficiency. In patients who had TSH hyperresponsiveness and/or high basal TSH levels and PRL hyperresponsiveness and/or high basal PRL levels, primary hypothyroidism was complicated in 58.4 and 42.3%, respectively. Hashimoto's thyroiditis was complicated in 29.8 and 20.5%, respectively, of these patients. Pituitary cell antibody (PCA) was detected in 36.6% of ACTH-deficient patients who were examined. Pituitary cell surface antibody (PCSA) to AtT-20 cells and GH3 cells was detected in 50.0 and 28.0% of the examined cases, respectively. The prevalence of PCA and PCSA did not differ between TSH-hyperresponsive patients and those with normal TSH basal levels and response, whereas PCA and PCSA were significantly more prevalent in PRL-hyperresponsive patients than in those with normal PRL levels and response. An empty sella was found in 30.2% of the examined case.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:[Hyperresponsiveness of TSH and prolactin and impaired responsiveness of GH in Japanese patients with isolated ACTH deficiency]. 133 97

Hybridization histochemistry has bridged molecular biology and neuroanatomy to provide nearly dynamic views of gene expression in the brain--perhaps especially in the hypothalamus. These snapshots of transcript levels with precise anatomical localization have revealed new insights into gene regulation in the hypothalamus under specific conditions. Magnocellular neurons in the paraventricular and supraoptic nuclei produce vasopressin and oxytocin. Transcript levels for these hormones are affected by hyperosmolality, as are those for many other neuropeptides. Patterns of gene expression in the magnocellular neurons in these nuclei during development and under different physiological conditions have been studied less extensively. The parvocellular neurons of the paraventricular nucleus produce corticotropin-releasing factor and thyrotropin-releasing hormone. Expression of the corticotropin-releasing factor gene is regulated by glucocorticoids. Physiological stresses, which activate the hypothalamo-pituitary-adrenal axis, also affect gene expression in the parvocellular paraventricular nucleus. Thyrotropin-releasing hormone is synthesized in a different set of parvocellular neurons in the paraventricular nucleus and in other neurons of the hypothalamus. Expression of the thyrotropin-releasing hormone gene is regulated by thyroid hormone. The suprachiasmatic nucleus contains neurons that produce vasopressin or vasoactive intestinal polypeptide in a circadian rhythm. Future studies using combinations of classical neuroanatomical techniques, hybridization histochemistry and immunohistochemistry will further our understanding of hypothalamic responses to various stimuli.
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PMID:Regulation of gene expression in the hypothalamus: hybridization histochemical studies. 142 21

Pseudohypoparathyroidism is a complex disorder of renal resistance to parathyroid hormone the mechanism of which is unclear. It is often associated with skeletal abnormalities and there may also be other hormonal defects. This is an extensive endocrinological investigation of five of six affected members in two generations of one family. The phenotypic variability of the syndrome is explored: four members had hypothyroidism; two had abnormal gonadal function; all five had abnormal prolactin response to TRH; one had abnormal hepatic response to glucagon infusion. All had normal hypothalamic-pituitary-adrenal axes, renal responsiveness to vasopressin and growth hormone responses to a variety of stimuli. Special note is made of oral pathology, and evidence of platelet aggregation abnormalities is presented which has not previously been described in the syndrome.
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PMID:Pseudohypoparathyroidism: its phenotypic variability and associated disorders in a large family. 204 19

The roles of oxytocin (OT) and vasopressin (AVP) on both basal and estrogen-induced prolactin (PRL) secretion were examined. Adult female Sprague-Dawley rats that were ovariectomized for 3 weeks and received estrogen treatment for 1 week were used. Intravenous administration of hormones and serial blood sampling were accomplished through indwelling intraatrial catheters which were implanted two days before. Plasma PRL levels were measured by radioimmunoassay. Oxytocin at a dose of 20 micrograms/rat stimulated a moderate PRL release in the morning and lower doses (5 and 10 micrograms) were without effect. Vasopressin was most effective at a dose of 5 micrograms/rat in stimulating PRL release, while consecutive injections of higher doses (10 and 20 micrograms) were less effective. In contrast, TRH, ranging from 1 to 8 micrograms/rat, induced a dose-dependent increases in PRL secretion. Using the effective dosages determined from the morning studies, repeated injections of either OT, AVP or their specific antagonists MPOMeOVT [( 1-(beta-mercapto-beta, beta-cyclopentamethylene propanoic acid), 2-(O-methyl)tyrosine, 8-ornithine]-vasotocin) and d (CH2)5Tyr(Me)AVP ([1-(beta-mercapto-beta, beta-cyclo-pentamethylene propionic acid), 2-(O-methyl)tyrosine, 8-arginine]-vasopressin), were given hourly between 1300 to 1800 h and blood samples were obtained hourly from 1100 to 1900 h. It was found that either OT or AVP significantly reduced the afternoon PRL surge, while their antagonists were not as effective. When OT or AVP were administered together with their specific antagonists, the inhibitory effects of either hormone on PRL surge were reversed. Thus it is concluded that both OT and AVP assume a non-specific stress-like effect on PRL release, in which basal secretion is stimulated and surge secretion is inhibited.
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PMID:Paradoxical effects of oxytocin and vasopressin on basal prolactin secretion and the estrogen-induced prolactin surge. 212 15

Histamine (HA), which acts as a neurotransmitter in the central nervous system, participates in the neuroendocrine regulation of prolactin (PRL) secretion. HA has a predominant stimulatory effect which is mediated via H2-receptors following central administration and via H1-receptors following systemic infusion of the amine. In addition, HA seems to exert a minor inhibitory effect on PRL secretion, an effect unmasked only during blockade of the receptor mediating the stimulatory effect. Following central administration the inhibitory effect is mediated via H1-receptors, while following systemic administration this effect is mediated via H2-receptors. In accordance with these findings, the H2-receptor antagonist cimetidine (CIM) has an inhibitory (following central administration) or stimulatory (following systemic administration) effect on PRL secretion. However, high doses of CIM possess an additional PRL stimulatory action not related to blockade of H2-receptors. This non-specific action is not exerted by the chemically different H2-receptor antagonist ranitidine. Since HA has no effect directly at the pituitary level, the actions of the amine may occur at different sites within the hypothalamus by an effect on hypothalamic transmitters regulating PRL secretion. Dopaminergic as well as serotoninergic neurons are involved in the mediation of the action of HA, since the dopamine (DA) concentration in the pituitary portal vessels is decreased by central or systemic infusion of HA, and since blockade of DA synthesis and of DA or serotonin (5-HT) receptors inhibit or prevent the PRL stimulatory action of HA infused centrally or systemically. However, other factors regulating PRL secretion (e.g. beta-endorphin, vasoactive intestinal peptide, vasopressin or TRH) may be involved in the mediation of the PRL response to HA. In men the effects of HA on PRL secretion are similar to the effects in male rats. Systemic infusion of HA stimulates PRL secretion via H1-receptors and inhibits PRL secretion via H2-receptors. The PRL-stimulatory effect of HA is caused by an inhibition of the dopaminergic system, while the PRL-inhibitory effect of HA may involve other transmitters than DA. In contrast to its stimulatory effect in men, HA had no effect on basal PRL secretion in women, but enhanced the PRL response to TRH. In rats or in humans the PRL stimulatory effect of HA is not caused by the cardiovascular actions of the amine.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Histaminergic regulation of prolactin secretion. 218 99

The roles of oxytocin and vasopressin on prolactin secretion were studied. Adult female Sprague-Dawley rats ovariectomized for two weeks and treated with a long-acting estrogen, polyestradiol phosphate for one week were used. Hormone administration and serial blood sampling were accomplished through indwelling intra-atrial catheters which were implanted two days before the experiment. Both oxytocin (20 micrograms/rat) and vasopressin (5 micrograms/rat) stimulated prolactin secretion within 10 min after injection and the effects were diminished by 30 min. In animals pretreated with a small dose of dopamine antagonist, sulpiride (1 microgram/rat), the effect of TRH on prolactin secretion was repeatedly shown to be potentiated. Same pretreatments with two different time intervals (30 and 60 min) between sulpiride and oxytocin/vasopressin administration, however, had no effect on oxytocin- or vasopressin-stimulated prolactin secretion. A vasopressin analog, 1-deamino-[D-Arg8]-vasopressin (dDAVP), with antidiuretic but no vasopressor activity was also used in the study. It was found that unlike vasopressin, dDAVP had no effect on prolactin secretion. In conclusion, both oxytocin and vasopressin can have a stimulatory effect on prolactin secretion when given in vivo. Unlike TRH, however, the action of oxytocin or vasopressin was not augmented by pretreatments of dopamine antagonist. The action of vasopressin on prolactin secretion may be a side effect of its vasopressor activity.
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PMID:Dopamine antagonism does not potentiate the effects of oxytocin and vasopressin on prolactin secretion. 226 68

The intracellular concentrations of cyclic AMP, polyphosphoinosides and free Ca2+ were unaffected during receptor-mediated endocytosis of the neoglycoprotein beta-D-galactosyl-bovine serum albumin (D-Gal-BSA) by isolated hepatocytes. Elevation of either intracellular cyclic AMP by glucagon or inositol phosphates and Ca2+ by vasopressin were without effect on the binding and internalization of D-Gal-BSA. The normal response of this cell to glucagon- and vasopressin-mediated mobilization of these second messengers was not modified in the presence of saturating concentrations of D-Gal-BSA. Receptor-mediated endocytosis of diferric transferrin (Fe3+-TRF) by both hepatocytes and HL60 cells was also shown to be independent of second messengers, although the unequivocal expression of the transferrin receptor by hepatocytes could not be satisfactorily demonstrated. The results of the present study are at variance with a suggested regulatory role for second messengers in receptor-mediated endocytosis of serum-derived ligands such as asialoglycoproteins and Fe3+-TRF. Receptor phosphorylation by protein kinase C in particular has been proposed to regulate the distribution and recycling of these receptors in actively endocytosing cells. We would suggest that if receptor phosphorylation has a regulatory role during endocytosis, it is likely to be mediated by a second-messenger-independent protein kinase analogous to casein kinase II. An alternative interpretation is that phosphorylation has no physiological significance and receptor-mediated endocytosis is a constitutive event coupled to membrane turnover.
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PMID:Receptor-mediated endocytosis of asialoglycoproteins and diferric transferrin is independent of second messengers. 254 88


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