Effects of vasopressin on human renal arteries.
The effects of vasopressin were studied in isolated rings from branches (2-3 mm in external diameter) of human renal arteries obtained from 18 patients undergoing nephrectomy for non-obstructive neoplasia. In arterial rings under resting tension, vasopressin produced concentration-dependent and endothelium-independent contractions with an EC50 of 9.1 X 10(-10) molL-1. The vasopressin V1 receptor antagonist d(CH2)Tyr(Me)AVP (10(-6) molL-1) displaced the control curve to vasopressin 564-fold to the right in a parallel manner. In precontracted arterial rings and previously treated with the V1 antagonist (10(-6) molL-1) vasopressin caused endothelium-independent relaxation. The relaxation to vasopressin was reduced significantly by indomethacin (10(-6) molL-1) and unaffected by the V1/V2 receptor antagonist desGly d(CH2)5-D-Tyr(Et)ValAVP(10(-6) molL-1) or by NG-nitro-L-arginine methyl ester (10(-4) molL-1). These observations indicate that vasopressin is primarily a constrictor of human renal arteries by V1-receptor stimulation. Vasopressin causes prostaglandin-mediated dilation of human renal arteries only if V1-receptor blockade is present. The effects of vasopressin on human renal arteries may be relevant in those clinical situations characterized by increased plasma vasopressin levels.
Medina
P
P
Departamento de Fisiología, Universidad de Valencia, Spain.
Vila
J M
JM
Martinez
M C
MC
Aldasoro
M
M
Chuan
P
P
Lluch
S
S
D000328:Adult; D000368:Aged; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000187:drug effects; D005260:Female; D006801:Humans; D007213:Indomethacin / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction / Q000187:drug effects; D009126:Muscle Relaxation / Q000187:drug effects; D009638:Norepinephrine / Q000494:pharmacology; D012077:Renal Artery / Q000187:drug effects*; D014662:Vasoconstrictor Agents / Q000494:pharmacology*; D014667:Vasopressins / Q000494:pharmacology*
D000894:Anti-Inflammatory Agents, Non-Steroidal; D014662:Vasoconstrictor Agents; D014667:Vasopressins; D009638:Norepinephrine; D007213:Indomethacin