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 pineal indoleamine, melatonin, has been shown to influence many physiological systems within the mammalian body. Few studies, however, have examined the influence of melatonin on renal function. This study investigated the effects of melatonin on water metabolism and renal function. Young adult male Syrian hamsters were maintained on a long photoperiod (LD 14:10) in metabolic cages. The animals received daily (1700) injections of either control vehicle or 25 micrograms of melatonin for 85 consecutive days. Melatonin administration resulted in significant increases in water consumption and urine production. Water budgets were also significantly influenced by melatonin, as were urinary osmolality, urinary sodium, and potassium concentrations, but urinary calcium concentrations were essentially unaltered. When excretion rates for sodium, potassium, and calcium were calculated, no differences were observed between the vehicle control and melatonin-treated groups. Injections of melatonin also significantly decreased plasma antidiuretic hormone (ADH). These results demonstrate that afternoon injections of melatonin can alter renal function, which may involve direct (i.e., on ADH secretion and/or thirst mechanisms) or indirect (i.e., behavioral) effects.
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PMID:Effects of melatonin on water metabolism and renal function in male Syrian hamsters (Mesocricetus auratus). 145 9

The effect of melatonin as well as pinealectomy on the basal and K(+)-evoked release of vasopressin and oxytocin from the neurointermediate lobes in vitro was determined. Pineal removal resulted in a diminution of vasopressin and oxytocin release from the neurointermediate lobes in vitro. Melatonin (10(-3) or 10(-6) M/l) increased vasopressin and oxytocin release from neurointermediate lobes of sham-operated rats. Nevertheless, when pinealectomized rats served as donors of the neurointermediate lobes, melatonin (10(-3) or 10(-6) M/l) increased vasopressin release under basal conditions. For the same tissue, melatonin did not affect the oxytocin release either under basal conditions or during depolarization due to excess potassium. When 10(-7) M/l melatonin was used, no changes in either vasopressin or oxytocin release were observed in vitro.
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PMID:Melatonin, pinealectomy, and release of neurohypophysial hormones: in vitro studies. 156 28

The author presents an account of selected important findings in endocrinology during the last year. The mediator of action of STH, IGF-I, was tested as a protein anabolic in a child with Laron's nanism. STH is about to be tested as a geriatric drug. A non-peptide vasopressin antagonist was described. Melatonin is being tested in sleep disorders. A combination of methimazol and thyroxine is more suitable for treatment of Graves-Basedow's disease than the goitrogen alone. Dermal vasoconstriction can be an indicator of the effectiveness of glucocorticoids in asthma. Significant advances were made in the sphere of the new hormone, NO: it is not only an effective vasorelaxing agent but also a neuromodulator and participates in the natural lymphocytic cytotoxicity. Marked advances were made as regards knowledge of the endogenous ligand for benzodiazepine receptors.
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PMID:[Endocrinology 1990-1991]. 180 40

Melatonin injected in a single intraperitoneal dose of 100 micrograms/100 g b.w. to euhydrated rats resulted in a decrease of neurohypophysial oxytocin content but the hypothalamic oxytocin storage as well as the hypothalamo-neurohypophysial storage of vasopressin were not changed. Following 8 d of once-daily melatonin treatment the hypothalamic and neurohypophysial oxytocin and vasopressin content was decreased. It might be therefore suggested that melatonin increases the release of neurohypophysial hormones and/or decreases their synthesis. Melatonin did not significantly modify the neurohypophysial vasopressin depletion rate in animals deprived of water up to 8 days. No consistent effects of melatonin on the decrease of hypothalamo-neurohypophysial content of oxytocin were noted under conditions of dehydration and simultaneous administration of melatonin up to 8 d.
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PMID:The influence of melatonin on the content of vasopressin and oxytocin in the hypothalamus and neurohypophysis in euhydrated and dehydrated male rats. 377 20

The release of progesterone, estradiol-17 beta, oxytocin, arginine-vasopressin, cAMP, and cGMP by cultured granulosa cells isolated from porcine ovaries without and in the presence of melatonin (0.001, 0.01, 0.1, 1, 10, and 100 ng/ml medium) was analyzed. It was found that melatonin is able to inhibit progesterone and stimulate estradiol secretion. Melatonin treatments significantly inhibited oxytocin release. Some inhibition of vasopressin and cAMP and significant stimulation of cGMP also resulted from melatonin treatment. The present observations suggest a direct effect of melatonin on the steroid, nonapeptide hormone, and cyclic nucleotide release from porcine ovarian cells.
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PMID:Direct influence of melatonin on steroid, nonapeptide hormones, and cyclic nucleotide secretion by granulosa cells isolated from porcine ovaries. 789 82

The effect of haemorrhage (1 ml per 100 g b. w.) on the vasopressin and oxytocin storage in the hypothalamus and neurohypophysis of melatonin-treated male rats was determined. Melatonin treatment (100 micrograms/100 g b. w., once daily over 8 days) resulted in a known decrease of vasopressin as well as oxytocin content both in the hypothalamus and neurohypophysis. Haemorrhage decreased the neurohypophysial vasopressin and oxytocin storage in animals injected with vehicle solution or otherwise not treated. In melatonin-treated rats, however, bleeding did not affect the actual (i.e., decreased by melatonin) vasopressin and oxytocin content in the hypothalamo-neurohypophysial system. The results demonstrate that melatonin may be involved in mechanisms determining the rate of the response of vasopressinergic and oxytocinergic neurones to bleeding.
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PMID:Hypothalamic and neurohypophysial vasopressin and oxytocin content as influenced by haemorrhage in melatonin-treated male rats. 836 9

The effect of haemorrhage and melatonin on the vasopressin and oxytocin storage in the neurohypophysis of pinealectomized male rats was determined. Sham operated or pinealectomized rats as well as rats pinealectomized and injected with melatonin (100 micrograms/100 g b. w., once daily over 8 days) or with melatonin vehicle (2.2% ethanol in 0.9% NaCl) were subsequently subjected to haemorrhage. Pinealectomy was followed by known decrease of both vasopressin and oxytocin content in the neurohypophysis as compared to sham operated rats. Similarly, haemorrhage decreased the neurohypophysial vasopressin and oxytocin storage in both sham operated and pinealectomized animals. Melatonin, injected to pinealectomized animals, did not modify the diminution of neurohypophysial vasopressin and oxytocin content caused by bleeding. The results demonstrate that in pinealectomized rats melatonin does not affect the rate of the response of vasopressinergic and oxytocinergic neurones to bleeding.
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PMID:The effect of haemorrhage and melatonin on neurohypophysial vasopressin and oxytocin content in pinealectomized male rats. 836 10

The secretion of neurohypophyseal hormone and ACTH in the rat has been shown to exhibit circadian rhythms, with high values during the day and low values throughout the night. The neurohypophyseal hormone daily rhythm is altered by exposure to constant light and by pinealectomy. It was, thus, proposed that the observed fall in vasopressin (AVP), oxytocin, and ACTH over the hours of darkness could be related to the release of melatonin seen at this time. Therefore, a study was performed to determine the effect of melatonin on AVP, oxytocin, and CRH-41 release from the isolated rat hypothalamus in vitro. Employing a previously validated technique, rat hypothalami were incubated in either medium alone or medium containing melatonin or one of two melatonin analogs. Hormone release was measured by RIA, and the ratios were calculated and compared by Student's t test, with Dunnett's correction for multiple comparisons. Melatonin showed a dose-dependent inhibition of both basal and stimulated AVP and oxytocin release in the concentration range 4.3 x 10(-10) to 2.5 x 10(-3) M, while having no significant effect on the release of CRH-41. The two melatonin analogs, 2-iodomelatonin and 5-methoxy-N-isobutanoyltryptamine, were also found to inhibit both basal AVP and oxytocin release, indicating that this effect probably depends upon the presence of melatonin receptors in the hypothalamus. This inhibitory modulation of AVP, in the absence of any effect on CRH-41, suggests that melatonin may affect water balance by means of directly inhibiting hypothalamic AVP release. Furthermore, circadian rhythmicity in pituitary-adrenal activity may depend on melatonin modulation of AVP, rather than changes in CRH-41.
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PMID:Melatonin and its analogs inhibit the basal and stimulated release of hypothalamic vasopressin and oxytocin in vitro. 844 Jan 90

The aim of this investigation was to study whether melatonin affects the release of oxytocin and vasopressin by the pituitary neurointermediate lobe of the Syrian hamster in vitro. The effect of melatonin was studied on the unstimulated (pre- and post-K+ -stimulated) release of oxytocin and vasopressin and on the response to K+ stimulation. Melatonin significantly inhibited unstimulated release of these hormones in all concentrations (10(-11) M, 10(-9) M and 10(-7) M) studied. K+ -stimulated release of oxytocin and vasopressin was significantly decreased by the 10(-9) M dose of melatonin. It is concluded that melatonin is active in modifying the release of these peptides in the Syrian hamster neurointermediate lobe, as it has been previously demonstrated in the rat hypothalamus.
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PMID:Melatonin inhibits oxytocin and vasopressin release from the neurointermediate lobe of the hamster pituitary. 874 40

In the present study, the effect of photoperiod on vasopressin content in the pituitary neurointermediate lobe (NIL), as well as the ability of pinealectomy to prevent and melatonin to mimic the short photoperiod-induced changes in NIL vasopressin were studied in male Syrian hamsters. The ability of melatonin to modify the hyperosmotically stimulated vasopressin release was also determined. Exposure to short photoperiod (SD) for 4 or 10 weeks increased vasopressin content in the hamster NIL. In long photoperiod (LD)-exposed hamsters, pinealectomy induced a decrease in NIL vasopressin content, whereas no effect of melatonin injections on vasopressin storage in the NIL was detected. In SD-exposed animals, pineal removal failed to alter vasopressin content in the NIL. Hypertonic saline administration led to the expected decrease in vasopressin content in the NIL both in vehicle- and melatonin-treated animals. The hyperosmotically stimulated release of vasopressin was not modified by previous treatment with melatonin. The data from the present study show that, in male Syrian hamsters, exposure of animals to SD increases the vasopressin content in the posterior pituitary, but these changes appear not to be mediated by SD-induced changes in melatonin secretion. Furthermore, the exposure of animals to SD prevents the pinealectomy-induced changes in NIL vasopressin content. Melatonin does not modify the hyperosmotically stimulated vasopressin release in the male Syrian hamster.
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PMID:Neurohypophyseal vasopressin in the Syrian hamster: response to short photoperiod, pinealectomy, melatonin treatment, or osmotic stimulation. 899 33


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