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 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

It is clear from the extant literature that various fish groups face chronic osmoregulatory problems that depend on the surrounding salinity. Their physiologic and hormonal responses are largely those seen in the mammals, but their terrestrial descendants have lost osmoregulatory structures such as gills and rectal glands and depend primarily on renal function. A data base is now emerging that strongly suggests that a putative atriopeptin plays a role in osmoregulation in fishes. This conclusion is supported by the fact that heterologous AP produces relevant physiologic responses (e.g. natriuresis, vasodilation, stimulation, or inhibition of Na+ secretion by intestine, gills, and rectal gland) in both teleosts and elasmobranchs. Moreover, cardiac and brain extracts from fish can produce similar effects in both fishes and mammals, and these tissues from various fish groups contain immunoreactive AP, as does plasma. Both physiologic and immunologic evidence suggests that the ventricle may be a significant source of AP in fishes, contrary to the situation in mammals. Finally, osmotic perturbations result in a change in plasma and tissue APir levels. The finding that plasma APir levels increase in sea water, and that heterologous AP stimulates salt secretion by the teleost gill and shark rectal gland, and inhibits salt uptake by the teleost intestine, suggests that AP may primarily play a role in salt, rather than fluid, secretion in fishes. The fact that in mammals AP inhibits prolactin secretion, but is itself stimulated by cortisol, supports this conclusion, since prolactin is generally considered to be the dominant osmoregulatory hormone in freshwater fishes, and cortisol serves this function in marine fishes. In addition, if AP inhibits brain AVT release in fishes, as it apparently inhibits vasopressin release in mammals, this also would be adaptive in marine fishes since AVT in fishes is diuretic, rather than antidiuretic. Interactions between AP and these hormones (prolactin, cortisol, and ATV) have not been studied in fishes to date, but these theoretical interactions do lend support to the hypothesis that AP may function primarily in salt homeostasis in fishes. At least one potential hormonal interaction counters this argument, however. Atriopeptin is known to inhibit the production and effects of angiotensin II in mammals, and since this hormone is apparently dipsogenic in fishes, it may play a critical role in osmoregulation in sea water. Finally, it is of some historical interest that in Keys' (67) original description of the eel heart-gill perfusion system in 1931 he commented that gill resistance remained constant for hours only if the heart itself was perfused.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:An emerging role for a cardiac peptide hormone in fish osmoregulation. 213 57

The effects of an opioid receptor antagonist, naloxone (NAL), were studied on the changes in pituitary hormone secretion induced by emotional stress. Male Wistar rats were trained with tone stimuli paired with electric footshocks and tested with the tone and environmental cue signals for emotional stress of fear acquired by learning as described previously (Onaka et al. 1988). Rats received s.c. injected NAL 30 min before testing at doses of 0, 0.2, 1.0, 5.0 and 25.0 mg/kg b.w. Half the rats were injected with 0.5 M NaCl (20 ml/kg b.w.) together with NAL. In these hypertonic rats plasma vasopressin level was slightly increased after NAL. The increment was statistically significant in control groups but not in experimental groups. However the suppression of vasopressin secretion by emotional stimuli was not changed by NAL. Plasma oxytocin levels were extremely high and not significantly different among experimental, unshocked control and untested control groups. NAL further increased the oxytocin level dose-dependently. NAL did not significantly change plasma adrenocorticotrophic hormone (ACTH) levels and hence did not modify the augmentative response in ACTH secretion to emotional stimuli. Plasma prolactin level was significantly elevated after emotional stimuli and NAL depressed the prolactin level in each of experimental and control groups. After NAL, the magnitude of the facilitatory response in prolactin secretion to emotional stimuli was decreased. Motor activity and its suppressive response to emotional stimuli were not influenced by NAL. In another half of rats under a normal osmotic condition the vasopressin response to emotional stimuli was not affected by NAL. NAL further augmented potentiation of oxytocin secretion after emotional stimuli dose-dependently.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Differential effects of naloxone on neuroendocrine responses to fear-related emotional stress. 216 20

We evaluated six patients in whom a diagnosis of Sheehan's syndrome had been made. The plasma levels of the following hormones were measured: basal thyroxine (T4), estradiol and cortisol; and also follicle-stimulating hormone (FSH), luteinizing hormone (LH), growth hormone (GH), thyrotropin (TSH), prolactin (PRL) and adrenocorticotropic hormone (ACTH), basally and after acute challenge with LH releasing hormone (LHRH), GRF (1-29)NH2 or insulin hypoglycemia, TSH releasing hormone (TRH) and lysine-8-vasopressin, respectively. Two patients underwent chronic LHRH stimulation by pulsatile subcutaneous administration with infusion pump. In 4 cases, computed tomography (CT) was performed although cranial X-ray study was normal. A severe and generalized pituitary involvement was found in all patients, 3 of whom had diabetes mellitus. Probably, more insidious cases go unnoticed. The presence of asymptomatic partial empty sella (ES) in all the CTs that were carried out raises the possibility that it is another evolutive feature of SS.
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PMID:[Relations between Sheehan's syndrome and empty sella turcica. A functional study apropos of 6 cases]. 217 69

The patterns of catecholamines (adrenaline and noradrenaline), peptide hormones (adrenocorticotropic hormone, antidiuretic hormone, beta-endorphin, growth hormone and prolactin), hydrocortisone (cortisol) and those of immunoglobulins (IgA, IgG and IgM) and total and differential leucocyte counts in the peripheral blood were investigated during and for 6 days after thyroid surgery in 20 patients (F/M: 18/2) performed under acupuncture anaesthesia, supplemented by small doses of pethidine (mean: 45.0 mg, s.d. 8.9). Throughout surgery the patients remained conscious. During surgery a significant increase in the level of catecholamines and the above-mentioned circulating hormones and a decrease of immunoglobulins were observed, whereas the leucocyte and differential counts demonstrated leucocytosis due to lymphocytosis, a decreased percentage of eosinophils and a remarkably reduced percentage of neutrophils. In the postoperative phase, levels of noradrenaline and beta-endorphin remained elevated, whereas the other circulating hormones gradually returned to normal values. Immunoglobulin levels and eosinophil counts returned to the preinduction values within 24 h, and those of neutrophil and lymphocyte counts within 2 days. Changes in number of monocytes and basophils could not be detected peri- and postoperatively.
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PMID:The patterns of stress response in patients undergoing thyroid surgery under acupuncture anaesthesia in China. 217 67

Psychological conditions which produce sustained activation have been clearly identified. Among these are the predictability and the controllability of the situation. We studied the impact of these psychological variables on hormone secretion (cortisol, ACTH, vasopressin, prolactin, and hGH plasma levels) under a standardized physical load. Sixteen subjects participated in four sessions each, one week apart, with the task of riding a bicycle until exhaustion. During three sessions, all experimental conditions were held identical to ensure the situation was a predictable as possible. During the fourth session, instructions induced a certain level of uncontrollability. Whereas physiological and performance measures did not vary with experience in the task, cortisol, ACTH, and vasopressin responses declined with increasing experience. This emphasizes the importance of the psychological definition of the situation for endocrine stress responses.
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PMID:Hormonal responses to exhausting physical exercise: the role of predictability and controllability of the situation. 217 35

PMS is probably a group of entities which include various symptoms that occur during the 7 to 10 days before menstruation and disappear a few hours after the onset of menstruation. The definition of PMS lacks objective criteria. The most common symptoms are irritability, bloating, aggressiveness, mastodynia, and headaches. The prevalence of PMS is estimated at 30 to 40 per cent. PMS is more prevalent among women working outside the home, alcoholics, women of high parity, and women with toxemic tendency; it probably runs in families. The etiology of PMS is no less obscure to us than when it was first described by Frank in 1931. No single theory has been established to explain the entire diversity of PMS symptomatology. The multitude of possible etiologic factors includes psychosocial bases, progesterone deficiency, prolactin excess, thyroid hypofunction, renin angiotensin alternations, antidiuretic hormone excess, decreased colloidosmotic pressure, endorphin activity alternations, serotonin metabolism alternations, prostaglandin action, vitamin deficiency, and such unconventional theories as the ovarian infection or the "yeast overgrowth" theory. A partial resolution of this divergence of hypotheses comes from the biopsychosocial model developed by Keye and Trunnel. According to this model, a biologic, perhaps genetically determined, predisposition to PMS is realized when past and present life experiences, attitudes, beliefs, coping styles, and social forces interact to stress a woman. The diagnosis of PMS is based on establishing a relationship between the luteal phase of the cycle and the symptoms. The evaluation of PMS patients includes the use of a monthly diary to scale the symptoms, a physical examination, and biochemical studies to rule out other disorders. Management includes education, reassurance, and drug therapy.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The premenstrual syndrome. 218 58

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

We examined 8 normal subjects and 16 patients with non-functioning pituitary tumors with a combined anterior pituitary test to evaluate the clinical usefulness of the test. Diagnoses included 9 of chromophobe adenoma, 3 of craniopharyngioma, 2 of Rathke's cleft cyst, and 1 each of intrasellar cyst and tuberculum sella meningioma. All subjects received hypothalamic releasing hormones: 1 micrograms/kg corticotropin releasing hormone (CRH), 1 micrograms/kg growth hormone releasing hormone (GRH), 500 micrograms thyrotropin-releasing hormone (TRH), 100 micrograms luteinizing hormone releasing hormone (LH-RH), and a relatively small dose (5 mU/kg) of lysine vasopressin (LVP). In the normal subjects, the addition of LVP potentiated the secretion of adenocorticotropic hormone (ACTH) induced by CRH, but had no significant effect on the secretion of other anterior pituitary hormones. In the combined test with 5 releasing hormones, the plasma ACTH and cortisol responses were not impaired in the majority of the patients before pituitary surgery. Serum thyroid-stimulating hormone (TSH), prolactin (PRL) and follicle-stimulating hormone (FSH) responses were not impaired in 82%, 70% and 67% of the patients, respectively, while the serum LH and GH responses were impaired in 67% and 73% of the patients, respectively. Following pituitary surgery, responses of these hormones to combined testing were similarly impaired in more than 75% of the patients. These results indicate that plasma ACTH, cortisol and serum TSH responses are fairly good before pituitary surgery but are impaired significantly after surgery. No subjects experienced any serious adverse effects related to the testing. These results suggest that combined testing with hypothalamic hormones is a convenient and useful method for evaluating pituitary function.
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PMID:Combined anterior pituitary function test using CRH, GRH, LH-RH, TRH and vasopressin in patients with non-functioning pituitary tumors. 220 Feb 36

To evaluate the interrelationships between anterior pituitary function and the antidiuretic system in patients harbouring hypothalamo-hypophyseal tumorous lesions, combined anterior pituitary stimulation tests were performed in the pre (n = 192 patients) and postoperative (n = 151 patients) state. Basal and stimulated plasma antidiuretic hormone, serum as well as urinary osmolality and diuresis were analyzed to determine the residual functional capacity of the antidiuretic system. In 106 patients with non-prolactin (PRL) secreting tumours basal and stimulated PRL secretion of the residual anterior pituitary was studied pre- and postoperatively. It was found that in the preoperative state latent (n = 12 patients) or manifest (n = 10 patients) types of diabetes insipidus (DI) were related to a significant decrease of maximal stimulated levels of thyroid stimulating hormone as well as basal and maximal stimulated levels of follicle stimulating hormone relative to patients without DI. In the postoperative state DI lasting longer than 10 days (n = 51 patients) was associated with decreased basal and maximal stimulated concentrations of cortisol, luteinizing and follicle stimulating hormone, whereas basal and maximal stimulated levels of PRL were significantly increased compared to those patients without DI (n = 61 patients). Decompression (n = 65 procedures) via the transnasal route was related with a lower frequency of the more severe types of DI (n = 7 patients) and a significant decrease of basal and maximal PRL levels in patients with non-PRL secreting tumours. The transcranial approach (n = 86 procedures) caused a higher rate of severe DI types (n = 33 patients) and an increase of PRL secretion from the residual anterior pituitary lobe. Patients without DI or DI of mild severity (n = 50), as a group, had a significant decrease of basal and maximal PRL levels compared with preoperative values (preoperative: basal = 14.3 +/- 1.5 ng/ml, max = 31.4 +/- 1.5 ng/ml, postoperative: basal = 9.6 +/- 1.1 ng/ml, max = 24.9 +/- 2.9 ng/ml). In patients with severer degrees of DI (n = 40) PRL levels were significantly increased, respectively (preoperative: basal = 15.3 +/- 3.1 ng/ml, max = 23.9 +/- 7.6 ng/ml, postoperative: basal = 19.7 +/- 3.4 ng/ml, max = 38.6 +/- 7.9 ng/ml). It was concluded that in the surgical treatment of non-PRL secreting hypothalamo-hypophyseal lesions the results of early postoperative assessment of basal and stimulated PRL levels may predict the type of postoperative DI.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Different types of postoperative diabetes insipidus and the relation to basal and stimulated serum prolactin levels in patients with hypothalamo-hypophyseal tumorous lesions. 225 40


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