Interaction of vasopressin, angiotensin and alpha-adrenergic system in sodium depletion in the rat.
1. The role of vasopressin in cardiovascular adaptation to sodium depletion was examined in rats after 6 days on a low sodium diet. Studies were performed after selective or combined blockade with d(CH2)5 Tyr(Me)AVP (AVPA), enalaprilat (CEI) and phentolamine (PHENTOL). AVPA alone had no effect on systemic haemodynamics or regional blood flow distribution. After CEI or PHENTOL pretreatment, AVPA led to significant falls in peripheral resistance and increases in cardiac output and renal blood flow. In sodium depletion, endogenous vasopressin acts as a vasoconstrictor hormone, particularly in the kidney, when either the renin-angiotensin or alpha-adrenergic system is inhibited.
D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000804:Angiotensin II / Q000502:physiology*; D000818:Animals; D001127:Arginine Vasopressin / Q000031:analogs & derivatives* / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects; D002302:Cardiac Output / Q000187:drug effects; D004039:Diet, Sodium-Restricted; D004656:Enalapril / Q000494:pharmacology; D008297:Male; D010646:Phentolamine / Q000494:pharmacology; D051381:Rats; D012079:Renal Circulation / Q000187:drug effects; D013564:Sympathetic Nervous System / Q000502:physiology*; D014655:Vascular Resistance / Q000187:drug effects; D014667:Vasopressins / Q000502:physiology*
D000317:Adrenergic alpha-Antagonists; D014667:Vasopressins; D000804:Angiotensin II; D001127:Arginine Vasopressin; D004656:Enalapril; C025043:vasopressin, 1-(1-mercaptocyclohexaneacetic acid)-2-(O- methyl-L-tyrosine)-8-L-arginine-; D010646:Phentolamine