Role of dopamine in the angiotensin II-induced vasopressin release in the conscious dehydrated dog.
The effect of the dopamine antagonist, haloperidol, on arginine-vasopressin (AVP) release induced by angiotensin II was studied in six dehydrated conscious dogs. Angiotensin II (10 ng/kg per min) alone caused a twofold increase (P less than 0.05) in plasma AVP concentration, a 25 mmHg increase (P less than 0.01) in mean arterial blood pressure (ABP) and a 70% decrease (P less than 0.01) in plasma renin activity (PRA). In the presence of haloperidol (3 micrograms/kg per min), angiotensin II caused similar changes in mean ABP (25 mmHg; P less than 0.01) and PRA (-65%, P less than 0.01), but a small insignificant decrease in plasma AVP (-22%). The AVP response to angiotensin II in the presence of haloperidol was significantly (P less than 0.05) different from its response to angiotensin II alone. Neither haloperidol alone nor the two vehicles had any effect on plasma AVP or mean ABP but PRA dropped slightly. The results suggest that a dopaminergic mechanism may be involved in angiotensin II-induced AVP release.
D000804:Angiotensin II / Q000494:pharmacology; D000818:Animals; D001127:Arginine Vasopressin / Q000097:blood*; D001794:Blood Pressure / Q000187:drug effects; D003681:Dehydration / Q000378:metabolism; D004285:Dogs; D005260:Female; D006220:Haloperidol / Q000494:pharmacology*; D008297:Male; D012083:Renin / Q000097:blood
D000804:Angiotensin II; D001127:Arginine Vasopressin; D012083:Renin; D006220:Haloperidol