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)

RIA was used to measure the level of beta 2-microglobulin, vasopressin, natriuretic factor, prostaglandin E2 and of the components of the renin-angiotensin-aldosterone system in full-term and premature neonates in the early neonatal period. In the first days of life, regulation of water-salt metabolism was discovered to be activated, especially in highly premature neonates. The early postnatal period is the critical period of ontogenesis where extreme tension of the neurohumoral systems may lead to the adaptation failure up to destabilization of the internal medium and grave metabolic disorders.
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PMID:[Characteristics of neurohumoral regulation of water-electrolyte metabolism in premature newborn infants]. 197 35

Physiological studies have clarified the role that the brain has in the interplay between salt balance and hypertension. Neural mechanisms and endocrine secretions play a pivotal role in the adaptation of mammals to changes in the intake and excretion of sodium. Maneuvers that alter the concentration of sodium in the plasma modify the sensitivity of baroreceptor reflexes and alter vascular reactivity. These changes may be mediated in part by the release of vasopressin. The research also suggests that the brain indirectly modulates the ability of the vascular endothelium to release vasoactive factors. Collectively, these studies illustrate the multiple effects of the sodium ion on the peripheral neural and central endocrine mechanisms that participate in the regulation of arterial pressure.
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PMID:Neurovascular mechanisms and sodium balance in the pathogenesis of hypertension. 198 11

Renomedullary interstitial cells cultured from the Dahl salt-resistant rat have higher levels of basal cytosolic calcium and prostaglandin E2 and are more responsive to vasopressin than interstitial cells from the Dahl salt-sensitive rat. We examined the potential role of inositol phospholipid hydrolysis in mediating these differences. Vasopressin-induced increases in labeled inositol phosphates were enhanced in renomedullary interstitial cells from Dahl salt-resistant compared with those from salt-sensitive rats. Addition of neomycin reduced basal production of labeled inositol phosphates and abolished the increase in inositol phosphates induced by vasopressin. Neomycin also prevented the peak decline pattern in cytosolic Ca2+ seen with vasopressin but did not influence basal cytosolic Ca2+. In the presence of neomycin, vasopressin induced a modest but prolonged increase in cytosolic calcium. In contrast to its marked effects on inositol phosphate production, neomycin was without effect on basal or vasopressin-responsive prostaglandin E2 production. Moreover, basal and vasopressin-induced increases in cytosolic Ca2+ remained higher in renomedullary interstitial cells from Dahl salt-resistant versus those from salt-sensitive rats exposed to neomycin. The results do not support a requirement for phospholipase C-induced inositol phospholipid hydrolysis in the mediation of vasopressin actions on prostaglandin E2 production by renomedullary interstitial cells and imply that the differences in cytosolic Ca2+ and prostaglandin E2 seen in these two cell lines are not related to differences in inositol phospholipid metabolism.
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PMID:Calcium and prostaglandin E2 in renomedullary interstitial cells. 199 61

Heat-stressed pregnant ewes deliver intrauterine growth-retarded lambs. Selected maternal and fetal changes were investigated during acute heat stress in order to elucidate the mechanism for this growth retardation. Uterine blood flow decreased 20 to 30% in pregnant ewes during 1 degree C increases in core temperature. The decreases were accompanied by 60 and 100% increases in serum oxytocin and antidiuretic hormone, respectively. These effects were mimicked by salt loading or injections of antidiuretic hormone or oxytocin, suggesting a role for either or both hormones in regulating uterine blood flow during pregnancy. Chronically heat-stressed pregnant ewes were delivered by Caesarean section. Their fetuses were approximately 20% smaller than thermoneutral controls. Within each pair of heat-stressed twins, one fetus weighted one-third less than its litter mate. No difference in weights were observed within the control twins. The livers and brains of the heat-stressed fetuses were disproportionate in size. The livers from the small heat-stressed twins contained only one-half the protein of the controls and one-fourth the protein of their litter mates. Muscle protein was decreased in the heat-stressed fetuses, and liver and muscle glycogen were elevated as were liver arginase, glutamate-pyruvate transaminase and muscle creatinine. These results are consistent with the following hypothesis: heat stress stimulates the release of maternal antidiuretic hormone or oxytocin, which reduces uterine blood flow and causes a shift in fetal metabolism from anabolic to catabolic pathways; one fetus of heat-stressed twins is more severely affected than its litter mate.
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PMID:Maternal endocrine and fetal metabolic responses to heat stress. 203 Jan 75

In summary, for reasons that are not clear, some persons seem to be extremely good at retaining sodium on a high-sodium diet or poor at excreting sodium on a high-sodium intake. This is more frequent in Western hemisphere blacks than in whites in the West or in blacks in Africa. These geographic/ethnic differences in sodium handling ability may be related to environmental factors or, more likely, to inherited differences in the ability to conserve sodium based on the evolutionary principle of survival fo the fittest for the ability to conserve sodium. The frequency of this salt-conserving (thrifty) genotype in Western hemisphere blacks may have been further increased as a consequence of severe selection pressures for survival based on the ability to conserve sodium during the slavery period of history in the West. One characteristic of the blood pressure control systems of Western hemisphere blacks is suppression of plasma renin activity without suppression of aldosterone production. In addition there is greater nephrosclerosis in blacks than whites and a more rapid decline in creatinine clearance with age. When more sodium is ingested than the kidneys are able to handle (excrete), there is a (transient) slight positive sodium balance; as a result sodium, chloride, and water are retained, resulting in an expansion of plasma volume (Fig. 7-3). The initial physiologic responses include (increased) secretion of atrial natriuretic peptides and the digitalis-like substance (natriuretic hormone), and inhibition of vasopressin and aldosterone secretion. The net effect is directly enhanced natriuresis and diuresis, and a reduction in plasma volume, with no significant effect on blood pressure. However, if there is a continuing tendency to sodium retention and volume expansion, the capacity of the aforementioned mechanisms to control plasma volume will be exceeded; then, the chronically elevated level of the digitalis-like substance will inhibit the sodium pumps in the arterial and venous smooth muscle cells and in the sympathetic neurons. The increased venous tone will help to reduce plasma volume directly by reducing central venous volume. Arterial tone will be increased by direct action of the digitalis-like substance on the arterial smooth muscle and, indirectly, via the hormone's action on the sympathetic neurons. Initially, of course, blood pressure will be maintained in the normal range (but will be labile) because of the compensating cardiovascular reflexes. Once the capacity of these reflexes to control blood pressure is exceeded, however, the blood pressure will begin to rise; this will induce a pressure natriuresis to help restore plasma volume to normal.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:The pathogenesis of hypertension: black-white differences. 204 19

To elucidate the contributions of renal, humoral, and arterial baroreceptor reflex components to salt-induced hypertension, we administered 10% NaCl intravenously for 10 days to sinoaortic-denervated rabbits with unilateral nephrectomy (n = 7), sinoaortic-denervated rabbits with intact kidneys (n = 7), and sham-operated sinoaortic-denervated rabbits with unilateral nephrectomy (n = 7). Serial changes in mean arterial pressure (MAP), heart rate, and blood pressure variability were recorded. In sinoaortic-denervated rabbits with unilateral nephrectomy, MAP increased significantly from 109 +/- 2 to 124 +/- 3 mm Hg (day 4) and remained elevated for the rest of the experiment. This elevation of MAP was accompanied by a reduction in the standard deviation of MAP, with significant elevations in plasma vasopressin, norepinephrine, and atrial natriuretic peptide concentrations and in sodium retention. In the other groups, there were no significant changes in these vasoactive hormones. In the sham-operated sinoaortic-denervated rabbits with unilateral nephrectomy, sodium retention was similar to that of sinoaortic-denervated rabbits with unilateral nephrectomy. Continuous infusion (1 microgram/kg/hr) of a V1 antagonist prevented the elevation of blood pressure and plasma norepinephrine, the accumulation of sodium, and the reduction of blood pressure lability, whereas a bolus injection (10 micrograms/kg) on day 4 reduced blood pressure from 128 +/- 3 to 115 +/- 2 mm Hg (p less than 0.005). These results imply that vasopressin plays a crucial role in the expression of salt-induced hypertension in rabbits with compromised baroreceptor and renal function.
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PMID:Role of vasopressin in salt-induced hypertension in baroreceptor-denervated uninephrectomized rabbits. 204 53

Patients with ileostomies show an early diuresis when sodium restricted; this, together with an obligatory ileal sodium loss, predisposes them to severe salt and water depletion. The role of arginine vasopressin in this circumstance and whether it is natriuretic, or antinatriuretic, is unclear. There is also controversy over its likely effect on small bowel fluid reabsorption. We have examined the effect of the non-pressor (V2) synthetic vasopressin analogue 1-deamino-8-D-arginine (desmopressin) on renal and ileal sodium and water excretion in ileostomy patients during acute adaptation to a low sodium diet. Patients were studied on two separate occasions (nonrandomised) with and without the administration of desmopressin (0.75 micrograms intramuscular, three times a day). In eight subjects without desmopressin there was pronounced diuresis on the first low sodium day, associated with a fall in renal sodium excretion and no change in ileal output or composition. In five (of the original) subjects with desmopressin there was pronounced antidiuresis, no change in renal sodium excretion, and no change in ileal output or composition. In both studies rises in plasma renin activity and salivary aldosterone concentration lagged behind the early decline in renal sodium excretion. We have confirmed the phenomenon of 'low sodium' diuresis after sodium restriction in ileostomy patients and shown that it can be prevented by desmopressin. Desmopressin has no direct or indirect effect on renal sodium excretion or ileal fluid and electrolyte loss in humans.
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PMID:'Low sodium' diuresis and ileal loss in patients with ileostomies: effect of desmopressin. 206 Aug 72

1. The role of cerebral insulin or insulin-like immunoreactive substance (ILI) on arginine-vasopressin (AVP) release using rats was investigated. Feeding rats with a high salt diet for 4 weeks significantly decreased the contents of ILI in both the hypothalamus and pituitary gland. Intracerebroventricular infusions of insulin (4 and 40 micrograms/min for 30 min) increased plasma AVP concentrations dose-dependently without hypoglycaemia, but decreased hypothalamic and pituitary contents of AVP. 2. These results indicate that ILI in the brain may play a role in the secretion of AVP, and that this mechanism could be operated to control a water-sodium balance.
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PMID:Intracerebroventricular infusions of insulin increase vasopressin release in rats. 207 4

Two brothers, patient 1 with fever and vomiting, and patient 2 with failure to gain weight were studied. After 4 hr of water deprivation test, the urinary osmolality of the patient 1 was only 105 mOsm/liter and his body weight showed a 4.6% reduction. In response to desamino-8-D arginine vasopressin intranasal administration, no significant elevation of urinary osmolality of patient 1 occurred. After low dose vasopressin tests, the maximal urinary osmolality of their father was in the normal range, but that of their mother was below the normal range. Moreover, the patients showed no significant increase of urinary osmolality after the same tests. The brothers were diagnosed as nephrogenic diabetes insipidus (NDI) and their mother was diagnosed as a carrier. An early diagnosis of NDI is important, since adequate managements such as low-solute diet with restricted protein and salt intake or such as water intake at frequent intervals can prevent the hyperosmolality which would develop the delayed mental and physical developments. The usefulness of the combination of indomethacin with thiazide diuretics is described.
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PMID:A family case of nephrogenic diabetes insipidus. 209 13

A blunted pressure natriuretic response is present in Dahl salt sensitive rats. To determine whether this results from tubular or glomerular mechanisms, late proximal, early distal, and late distal micropuncture were performed in salt resistant (R), salt sensitive (S), or salt sensitive rats with renal perfusion reduced to that of R rats (S-AC). Differences in neuro-endocrine background between groups were eliminated by renal denervation and by fixing plasma aldosterone, norepinephrine, and vasopressin levels by infusion. Renal perfusion pressure was greater (P less than 0.05) and inulin clearance less (P less than 0.05) in S than R rats. Urinary sodium excretion, however, was not different. S-AC had renal perfusion pressures that were similar to R rats and inulin clearance similar to S rats. Urinary NaCl excretion was less (P less than 0.05) than either group. Single nephron inulin clearance, fluid, and chloride delivery to late proximal sites were not different between groups. Absolute and fractional chloride delivery to early distal sites was less (P less than 0.05) in S-AC than R or S but not different between R and S. Late distal chloride delivery was not different between any group. Calculated loop chloride reabsorption was greater in S-AC than R or S. Thus, the lower urinary NaCl excretion in S-AC rats is in part due to increased loop chloride reabsorption. This effect is probably intrinsic to the S kidney as it occurs despite renal denervation when plasma levels of vasopressin, norepinephrine, and aldosterone are fixed. The increased loop chloride uptake is abolished when perfusion pressure increases.
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PMID:Greater loop chloride uptake contributes to blunted pressure natriuresis in Dahl salt sensitive rats. 210 61


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