Search results for " arginine vasopressin"
showing 10 items of 15 documents
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-…
Desmopresssin and hemodilution: implications in doping.
2009
Blood doping improves physical performance in sport. This is the reason why the antidop- ing authorities subject athletes to blood tests. Plasma volume expanders are prohibited agents used to reduce an artifi cial increase in hemato- logical values using diff erent illegal practices. The aim of our study was to test whether desmo- pressin (DDAVP)-induced hemodilution would alter the concentration of hematological param- eters used to detect blood doping in sports. This was an intra-subject crossover study. Venous blood samples were obtained from eight physi- cally active males on two occasions. On the fi rst o ccasion the subjects ingested 1.5 L of mineral water and 4.3 μ g / kg of DDAVP. O…
Relaxation of human isolated mesenteric arteries by vasopressin and desmopressin.
1994
1. The effects of vasopressin and deamino-8-D-arginine vasopressin (DDAVP, desmopressin) were studied in artery rings (0.8-1 mm in external diameter) obtained from portions of human omentum during the course of abdominal operations (27 patients). 2. In arterial rings under resting tension, vasopressin produced concentration-dependent, endothelium-independent contractions with an EC50 of 0.59 +/- 0.12 nM. The V1 antagonist d(CH2)5Tyr(Me)AVP (1 microM) and the mixed V1-V2 antagonist desGly-d(CH2)5D-Tyr(Et)ValAVP (0.01 microM) displaced the control curve to vasopressin to the right in a parallel manner without differences in the maximal responses. In the presence of indomethacin (1 microM) the…
Separation of selected peptides by capillary electroendoosmotic chromatography using 3 μm reversed-phase bonded silica and mixed-mode phases
1999
The retention behaviour and selectivity of selected basic, neutral and acidic peptides have been studied by capillary electroendoosmotic chromatography (CEC) with Hypersil C8, C18, Hypersil mixed-mode, and Spherisorb C18/SCX columns, 250 (335) mm x 100 microns, packed with 3 microns particles, and eluted with mobile phases composed of acetonitrile-triethylamine-phosphoric acid (TEAP) at pH 3.0 using a Hewlett-Packard Model HP3DCE capillary electrophoresis system. The selected peptides were desmopressin (D), two analogues (A and B) of desmopressin, oxytocin (O) and carbetocin (C). The peptides eluted either before or after the electroendoosmotic flow (EOF) marker, depending on the concentrat…
Can we compare haemophilia carriers with clotting factor deficiency to male patients with mild haemophilia?
2020
Introduction Certain haemophilia carriers demonstrate an increased bleeding tendency, mainly related to clotting factor deficiency. No study has so far formally compared the bleeding phenotype of women and girls with mild FVIII or FIX deficiency and associated management with that of male patients affected by mild haemophilia A and B. Material and methods We retrospectively evaluated 44 women and girls with mild FVIII or FIX deficiency (FVIII or FIX 0.05-0.5 IU/mL) and 77 male patients with mild haemophilia A or B and compared them with respect to clotting factor level, age at and trigger for diagnosis, as well as treatment modalities. Results After excluding gender-related haemorrhagic sym…
The role of arginine-vasopressin for pineal melatonin synthesis in the rat: involvement of vasopressinergic receptors.
1991
Abstract The endogenously synthesized nonapeptide arginine vasopressin (AVP) is thought to be involved in transduction of photic information to the pineal gland. The enhancement of circulating AVP leads to a suppression of the nocturnal melatonin surge the mechanisms of which are unknown so far. We therefore studied the effect of dDAVP, an AVP analog with antidiuretic but without vasopressor activity, on pineal melatonin synthesis in Sprague-Dawley and AVP-deficient Brattleboro rats. The nocturnal intra-arterial application of dDAVP mimicked the inhibitory effect of AVP on the activity of the rate-limiting enzyme for pineal melatonin synthesis, N-acetyltransferase (NAT), in both rat strains…
Evaluation of antidiuretic hormone before and after long-term treatment with desmopressin in a group of enuretic children
1998
Objective To determine the effect of long-term desmopressin therapy in enuretic patients on the levels of antidiuretic hormone (ADH) during and after the end of therapy. Patients and methods The study comprised 25 outpatients (18 boys and seven girls) aged 8–12 years at the start of therapy and 12–16 years at the end. The morning (08.00 hours) plasma ADH level was determined before treatment (T0) with desmopressin and 2 years after (T1) ending the therapy. Seven of the 25 patients evaluated had monosymptomatic (simple enuresis, SE) and 18 had other symptoms (complex enuresis, CE). Results In the patients with SE, the mean (SD) duration of therapy was 305 (183) days and they were re-evaluate…
Enuresis Subtypes Based on Nocturnal Hypercalciuria: A Multicenter Study
2003
Purpose: Desmopressin may not be effective for nocturnal enuresis associated with polyuria and hypercalciuria. Nighttime hypercalciuria in an enuretic population from 5 centers and its correlation with nighttime polyuria were verified. Materials and Methods: A total of 450 enuretic patients (278 males, 172 females, mean age 9.7 years) were evaluated with 72-hour micturition charts, urinalysis, serum creatinine and osmolarity, diurnal and nocturnal electrolytes with fractional Na+ and K+ urinary excretion, and nocturnal (4 a.m.) plasma vasopressin. Creatinine electrolytes and osmolarity were measured in daytime (8 a.m. to 8 p.m.) and nighttime (8 p.m. to 8 a.m.) urine volumes. Patients were …