Search results for " vasopressin"
showing 10 items of 48 documents
Stabilizing selection on microsatellite allele length at arginine vasopressin 1a receptor and oxytocin receptor loci
2017
The loci arginine vasopressin receptor 1a ( avpr1a ) and oxytocin receptor ( oxtr ) have evolutionarily conserved roles in vertebrate social and sexual behaviour. Allelic variation at a microsatellite locus in the 5′ regulatory region of these genes is associated with fitness in the bank vole Myodes glareolus . Given the low frequency of long and short alleles at these microsatellite loci in wild bank voles, we used breeding trials to determine whether selection acts against long and short alleles. Female bank voles with intermediate length avpr1a alleles had the highest probability of breeding, while male voles whose avpr1a alleles were very different in length had reduced probability of …
Surge of Peripheral Arginine Vasopressin in a Rat Model of Birth Asphyxia
2018
Mammalian birth is accompanied by a period of obligatory asphyxia, which consists of hypoxia (drop in blood O2 levels) and hypercapnia (elevation of blood CO2 levels). Prolonged, complicated birth can extend the asphyxic period, leading to a pathophysiological situation, and in humans, to the diagnosis of clinical birth asphyxia, the main cause of hypoxic-ischemic encephalopathy (HIE). The neuroendocrine component of birth asphyxia, in particular the increase in circulating levels of arginine vasopressin (AVP), has been extensively studied in humans. Here we show for the first time that normal rat birth is also accompanied by an AVP surge, and that the fetal AVP surge is further enhanced in…
V2-receptor–mediated relaxation of human renal arteries in response to desmopressin
1999
The effects of deamino-8-D-arginine vasopressin (desmopressin), a V2 receptor antidiuretic agonist, were studied in isolated rings from branches of renal arteries obtained from 22 patients undergoing nephrectomy. The rings were suspended in organ bath chambers for isometric recording of tension. In precontracted rings with norepinephrine (10(-6) to 3 x 10(-6) mol/L), desmopressin (10(-11) to 3 x 10(-7) mol/L) caused endothelium-dependent relaxation (81%+/-4% reversal of the initial contraction in arteries with endothelium; 20%+/-4% in arteries without endothelium; P < .05). The relaxation to desmopressin in rings with endothelium was reduced significantly by indomethacin (10(-6) mol/L) and …
Endothelium-dependent relaxation of human saphenous veins in response to vasopressin and desmopressin
1997
Purpose: The goal of this study was to determine the effects of vasopressin and the selective V 2 -receptor agonist desmopressin on human saphenous veins, with special emphasis on endothelium-mediated responses. Methods: Human saphenous vein segments were obtained from 35 patients undergoing coronary bypass surgery. Paired segments, one normal and the other deendothelized by gentle rubbing, were mounted for isometric recording of tension in organ baths. Concentration-response curves to vasopressin and desmopressin were determined in the presence and in the absence of either the V,-receptor antagonist d(CH 2 ) 5 Tyr(Me)AVP (10 −6 mol/L), the V 1 -V 2 receptor antagonist desGly-d(CH 2 ) 5 D-T…
Desmopressin in the Treatment of Nocturia: A Double-Blind, Placebo-Controlled Study
2007
Objectives: To investigate efficacy, safety, and impact on quality of sleep of desmopressin in the treatment of nocturia. Methods: Adults aged >= 18 yr with nocturia (>= 2 voids/night) received desmopressin tablets (0.1, 0.2, or 0.4 mg) during a 3-wk dose-titration period. Patients should show sufficient response during the dose-titration period (>= 20% reduction in nocturnal diuresis) and a return of nocturnal diuresis to >= 80% of baseline levels during washout. Eligible patients then entered a 3-wk double-blind treatment period and received either desmopressin or placebo. Results: 127 patients were randomised to either desmopressin (n = 61) or placebo (n = 66). Twenty (33%) desmopressin-…
A female with X‐linked Nephrogenic diabetes insipidus in a family with inherited central diabetes Insipidus: Case report and review of the literature
2020
There are two forms of diabetes insipidus, central (neurohypophyseal), and nephrogenic, caused by pathogenic variants in the AVP gene and the AVPR2 or AQP2 genes, respectively. We report on a four-generation family, seven individuals had central diabetes insipidus (CDI) and the female index patient seen from age 16 to 26 years had (mild) nephrogenic diabetes insipidus. In her father with CDI, a known pathogenic heterozygous AVP variant c.232_234del p.(Glu78del) was identified, confirming the diagnosis of CDI in him and the other affected family members. In the proband, molecular analysis disclosed a novel heterozygous AVPR2 gene variant, c.962A > T p.(Asn321Ile) and an extremely skewed X-in…
Vasopressin receptors involved in adrenergic neurotransmission in the circular muscle of the human vas deferens
1998
We studied the effects of vasopressin on the adrenergic responses of in vitro preparations of circular muscle from the vas deferens obtained from 28 men undergoing elective vasectomy. Vasopressin (3 x 10(-9)-3 x 10(-8) M) enhanced the phasic contractions elicited by electrical field stimulation and noradrenaline. This potentiation was blocked by the vasopressin V1 receptor antagonist d(CH2)5Tyr(Me)vasopressin (10(-6) M) but not by the vasopressin V2 receptor antagonist [d(CH2)5, D-Ile2,Ile4,Arg8]vasopressin (10(-6) M). The Ca2+ antagonist nifedipine (10(-6) M) did not affect the potentiation of electrical field stimulation induced by vasopressin and noradrenaline but reduced KCl-induced con…
Contractile responses of human thyroid arteries to vasopressin
2013
Abstract Aims In the present study we investigated the intervention of nitric oxide and prostacyclin in the responses to vasopressin of isolated thyroid arteries obtained from multi-organ donors. Main methods Paired artery rings from glandular branches of the superior thyroid artery, one normal and the other deendothelised, were mounted in organ baths for isometric recording of tension. Concentration–response curves to vasopressin were determined in the absence and in the presence of either the vasopressin V 1 receptor antagonist d(CH 2 ) 5 Tyr(Me)AVP (10 − 8 M), the nitric oxide synthase inhibitor N G -monomethyl- l -arginine ( L -NMMA, 10 − 4 M), or the inhibitor of prostaglandins indom…
Endothelium-independent contractions of human cerebral arteries in response to vasopressin.
1990
We studied the effects of vasopressin in isolated segments from branches (500-700 micrograms in external diameter) of human middle cerebral arteries obtained during autopsy of 15 patients who had died 3-8 hours before. Paired segments, one normal and the other de-endothelized by gentle rubbing, were mounted for isometric recording of tension in organ baths. In 11 normal segments, vasopressin produced concentration-dependent contractions with an EC50 of 7.0 X 10(-10) M. Removal of the endothelium from 12 segments did not significantly affect vasopressin-induced contractions. Vasopressin produced further contractions in arterial segments with (n = 4) or without (n = 5) endothelium precontract…
Glucose polymer syrup attenuates prolonged endurance exercise-induced vasopressin release
1989
We investigated the effect of glucose and glucose polymer ingestion on plasma arginine vasopressin (pAVP) levels, on plasma osmolality (p-osm), and on performance during two prolonged endurance events. The study subjects were 37 Finnish elite endurance athletes, of whom 18 were orienteers and 19 cross-country skiers. Plasma AVP increased in both combined glucose and glucose polymer groups, but the increase in the glucose polymer group was significantly smaller (P less than 0.001) than that in the glucose group. A significant change in p-osm caused a significant change in pAVP and vice versa. Both the orienteers and the skiers on glucose polymer tended to have more success in the competition…