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)

Activation of the hypothalamus-pituitary-adrenal (HPA) axis is suggested to play a role in the stress-related inhibition of LH secretion. The aim of our study was to investigate the effects of vasopressin and oxytocin, which are increased in pituitary portal plasma in response to stress, and of glucocorticoids, the final product of HPA activation during stress, on basal plasma LH levels and on pituitary LH response to the GnRH test in amenorrheic (n = 33) and fertile (n = 13) women. Plasma LH levels were evaluated by radioimmunoassay in 2 different experimental conditions: 1. Basal secretion; 2. The GnRH test (10 micrograms + 10 micrograms after a 120-minute interval). These 2 evaluations were done in the presence of both placebo and a pharmacological dose of desmopressin (an analogue of vasopressin) (16.6 ngr/minute), oxytocin (0.2 ngr/minute) or hydrocortisone (4.1 mg/minute). None of these drugs modified basal plasma LH levels either in amenorrheic patients or in controls. Hydrocortisone inhibited the GnRH-induced LH increase in amenorrheic women. These data suggest that the glucocorticoids might play a role in LH secretion and indicate a possible participation of the HPA axis in the impairment of the hypothalamus-pituitary-gonadal axis in women with psychogenic amenorrhea.
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PMID:Glucocorticoids but not vasopressin or oxytocin inhibit luteinizing hormone secretion in patients with psychogenic amenorrhea. 272 8

To determine the importance of alpha 1-adrenergic receptors in the endocrine responses of fetal lambs to hemorrhage, eight chronically instrumented fetal lambs were bled of 20% of their measured blood volume after pretreatment with prazosin (24.8 +/- 2.1 days' gestation) or inert vehicle (124.2 +/- 2.2 days' gestation) according to a randomized, crossover protocol. Cortisol levels increased threefold with prazosin injection and remained elevated after hemorrhage but did not change with hemorrhage after vehicle infusion. Plasma renin activity was unaffected by the injection of prazosin but increased in both groups after hemorrhage. Vasopressin levels were unchanged in the control group throughout the experiment but increased tenfold with hemorrhage after pretreatment with prazosin. alpha 1-Adrenergic receptor blockade removes adrenergic inhibition of cortisol secretion and changes the hypotensive threshold for the secretion of vasopressin.
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PMID:Endocrine responses of fetal lambs to hemorrhage after alpha 1-adrenergic receptor blockade. 290 72

Three male subjects were passively tilted from a supine to a 90 degree head-up standing position on 2 d each at 1 and 31 ATA, then on 1 d of the postdive period. On each day the subjects were tilted once in the morning (0800-1000) and once in the evening (2000-2200). Before each tilt experiment, the subjects were first intravenously cannulated for blood sampling, then assumed the supine position. A blood sample was taken after 10 min in the supine position, and another sample was taken after 15 min of motionless, supported standing. The plasma was analyzed for antidiuretic hormone (ADH), plasma renin activity (PRA), plasma cortisol, and aldosterone. ADH, PRA, and cortisol were significantly increased by tilt, but the responses varied with time of day or atmospheric pressure. Cortisol increased only in the morning tilt (P less than 0.005) and was not affected by pressure. At 1 ATA, PRA was elevated in the morning tilt experiment (P less than 0.005) and not the evening tilt, but the overall response to tilt was greater at 31 ATA than at 1 ATA (P less than 0.005). The ADH response to tilt (P less than 0.025) was unaffected by time of day, but was eliminated at 31 ATA. The basal levels of ADH were also lower at 31 ATA (P less than 0.005). The mechanism of these responses remains unclear, but the eliminated postural stimulation of ADH may account for the eliminated circadian excretory pattern of the hormones. The altered responses to body fluid shifts possibly contribute to the increased aldosterone and decreased ADH frequently observed at hyperbaria.
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PMID:Seadragon VI: a 7-day dry saturation dive at 31 ATA. VI. Hyperbaria enhances renin but eliminates ADH responses to head-up tilt. 331 56

The variation in vasopressin concentrations of ventricular cerebrospinal fluid and plasma throughout a 24-h period was studied in 10 patients with hydrocephalus. In 6 control patients, the diurnal variation in plasma vasopressin concentrations was studied. Vasopressin concentrations were determined by radioimmunoassay in plasma and in extracted and unextracted cerebrospinal fluid. Cortisol and osmolality in plasma were also measured. Vasopressin concentrations measured in extracted cerebrospinal fluid showed only small intra- and interindividual variation, while the corresponding values for unextracted cerebrospinal fluid were 2-5-fold higher and showed more variation. Plasma vasopressin concentrations varied considerably throughout the 24-h period in the individual hydrocephalic patient and between the patients. The pattern of variation was inconstant with no circadian rhythm, and the variation was not related to any changes in plasma osmolality, blood pressure or intracranial pressure. In some of the patients, the normal diurnal pattern of variation in plasma cortisol was broken, however, without a relation to the observed fluctuations in vasopressin concentrations. The abnormal variation of plasma vasopressin and cortisol was considered to reflect stress in connection with the intracranial pressure monitoring procedure. In the control patients, plasma vasopressin showed only small variations and plasma cortisol showed a normal diurnal rhythm. It is concluded that cerebrospinal fluid vasopressin concentration in patients with hydrocephalus is very constant throughout the day, even when plasma vasopressin concentrations show marked episodic increases. Thus, a circadian rhythm in the cerebrospinal fluid vasopressin concentration, as reported in several animal species, could not be confirmed in these patients.
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PMID:24-hour cerebrospinal fluid levels of vasopressin in hydrocephalic patients. 403 58

To evaluate the role of antidiuretic hormone (ADH) in the defect in water excretion which is characteristic of glucocorticoid deficiency, the effects of hydrocortisone and ethanol upon urinary dilution during a sustained water load were studied in patients with anterior hypopituitarism. A spectrum of defects in urinary dilution was found in the seven patients with anterior hypopituitarism, and the subjects were separable into two groups. Four patients were unable to excrete a urine hypotonic to plasma (group I) while three diluted the urine (group II). In two of the group II patients, despite maintenance of hydration, urinary osmolality later rose to hypertonicity. Physiological doses of hydrocortisone improved urinary dilution in all patients. Submaximal doses of oral hydrocortisone, when given to the group I patients, converted their response to hydration to one characteristic of the group II patients, i.e., an initial hypotonic urine followed by a secondary rise to hypertonicity. Ethanol, a known inhibitor of ADH secretion, had no effect in the group I patients. When two of these patients were pretreated with sub-maximal doses of hydrocortisone, however, so that they were able to transiently dilute the urine, ethanol prevented the secondary rise in urine osmolality. Similarly, the administration of ethanol to the untreated group II patients, when the urine was hypotonic, improved diluting ability as characterized by a lowering of urinary osmolality and an increased excretion of solute-free water in all three patients. Hydrocortisone did not improve urinary dilution in three patients with complete hypophyseal diabetes insipidus and one with both anterior and posterior insufficiency receiving constant infusions of vasopressin. These data suggest, therefore, that inappropriately elevated levels of ADH play a major role in the defect in water excretion of anterior hypopituitarism. Glucocorticoids appear to be necessary for a normal neurohypophyseal response to inhibitory stimuli.
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PMID:Role of antidiuretic hormone in the abnormal water diuresis of anterior hypopituitarism in man. 509 63

A complete endocrinological exploration was performed in a 23 year old male patient who presented clinical signs of an acquired panhypopituitarism which appeared two months after a severe head trauma, in order to determine whether the deficit lay in the hypothalamus or in the pituitary. TSH had normal basal levels, but presented a delayed rise after TRH administration. PRL rose normally after TRH administration, but presented a blunted response to both metoclopramide and insulin tolerance test. Cortisol rose significatively after lysine vasopressin, but failed to rise during insulin hypoglycaemia. These results are consistent with a hypothalamic defect. Extensive endocrinological data are often lacking in the few similar cases reported in the literature. Prl and TSH were usually found to have normal basal levels while other pituitary hormones were profoundly lowered. This was interpretated as a pituitary defect with some intact areas of the anterior lobe. However, this may also suggest a hypothalamic defect which could have been assessed by mor discriminative tests.
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PMID:Panhypopituitarism secondary to head trauma: evidence for a hypothalamic origin of the deficit. 624 99

In eight experiments in which a paired crossover design was used, we studied the ability of physiologic levels of cortisol to block adrenocorticotropic hormone (ACTH) and vasopressin responses to hypotension in fetal lambs. On different days, each fetus received a 4-hour infusion of cortisol or ethanol-saline solution vehicle, and then hypotension was induced with nitroprusside. Mean levels of ACTH before manipulation were 20 +/- 10 pg/ml and 18 +/- pg/ml in the saline solution- and cortisol-treated animals, respectively. Mean values of ACTH increased significantly to 70, 88, and 127 pg/ml at 2.5, 5, and 10 minutes of hypotension after pretreatment with saline solution. Cortisol pretreatment abolished the fetal ACTH response to hypotension. Mean levels of vasopressin during the control period were similar in the two groups of animals (5.7 +/- 1.5 pg/ml versus 5.9 +/- 1.3 pg/ml) and rose to comparable levels (69.4 +/- 15.6 pg/ml versus 65.2 +/- 7.7 pg/ml) during hypotension. Thus, increases in plasma cortisol levels within a physiologic range can suppress hypotension-induced ACTH but not vasopressin release in the fetus.
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PMID:Cortisol infusion blocks adrenocorticotropic hormone but not vasopressin responses to hypotension in fetal lambs. 632 Jun 43

The purpose of this study was to test the hypothesis that physiological increases in the fetal plasma cortisol concentration after basal and stimulated levels of PRA and vasopressin. Seven fetal sheep, between 121 and 131 days gestation, were infused with cortisol (4 micrograms/min) or vehicle for 5 h. One hour after the end of cortisol or vehicle infusion, sodium nitroprusside was infused into the fetus (100 micrograms/min, iv) to stimulate fetal hormone secretion. Cortisol, but not vehicle, infusion increased the fetal plasma cortisol concentration and decreased fetal PRA, but did not alter the fetal plasma vasopressin concentration. Cortisol-infused fetuses responded to nitroprusside with slightly smaller PRA responses but with equal vasopressin responses compared to those of vehicle-infused controls. Fetal blood pressure was not affected by either cortisol or vehicle infusion. Nitroprusside caused a slightly greater reduction in pressure in fetuses receiving cortisol infusion compared to those receiving the vehicle. We conclude that physiological increases in fetal plasma cortisol decrease fetal PRA without altering the fetal plasma vasopressin concentration. The results suggest that repeated fetal stress might produce progressive reduction of fetal PRA activity and might, therefore, alter cardiovascular homeostasis.
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PMID:Physiological inhibition of ovine fetal plasma renin activity by cortisol. 638 42

In a randomized trial of pulsatile vs nonpulsatile cardiopulmonary bypass for coronary artery surgery, we studied hemodynamic and hormonal responses. Anesthesia did not produce a response but, from the time of the incision, cortisol and antidiuretic hormone levels and plasma renin activity all increased. Cortisol levels continued to rise after surgery, whereas the other began to fall. Systemic vascular resistance fell dramatically during cardiopulmonary bypass but rapidly rose after bypass with a reciprocal change in cardiac index. We did not see the changes ascribed to nonpulsatile bypass by others. There ws no difference between our pulsatile and nonpulsatile cases. High-flow cardiopulmonary bypass, vasodilating inhalation anesthesia and continuation of Inderal therapy may account for our results.
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PMID:Pulsatile cardiopulmonary bypass: failure to influence hemodynamics or hormones. 699 24

A patient with Cushing's disease is described who underwent transsphenoidal adenomectomy of a basophilic microadenoma with a diameter of 3 mm. In a piece of surrounding normal pituitary tissue removed at operation, multiple small nests of adenomatous basophilic cells were found both in the adeno- and neurohypophysis. No clinical improvement was observed. Cortisol secretory rate, plasma ACTH, the absent response of plasma cortisol to insulin-induced hypoglycemia, and the responses of plasma cortisol to lysine vasopressin and TRH remained unchanged. The observations in this patient point to the presence of multiple ACTH-secreting adenomatous cell nests and microadenomas throughout pituitary gland and bring back into view the concept of primary stimulation of hypothalamic corticotropin-releasing factor as the primary derangement in some patients with Cushing's disease.
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PMID:Failure of clinical remission after transsphenoidal removal of a microadenoma in a patient with Cushing's disease: multiple hyperplastic and adenomatous cell nets in surrounding pituitary tissue. 736 32


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