Mechanisms involved in two-kidney renal hypertension induced by constriction of one renal artery.
Changes in plasma renin activity (PRA) and sodium balance were studied in hypertensive rabbits and dogs with one renal artery constricted and the other kidney intact (two-kidney hypertension); aldosterone secretion was measured also in the chronic hypertensive rabbits. Both PRA and aldosterone secretion were normal in some chronic hypertensive rabbits but elevated in others. Sodium balance studies revealed that some severely hypertensive rabbits with elevated PRA were in spontaneous negative sodium balance. Unlike the rabbit, PRA was never increased in the chronic hypertensive dog and sodium balance was normal. Infusion of [Sar1, Ala8]angiotensin II (P-113) decreased arterial pressure and aldosterone secretion in those hypertensive rabbits with elevated PRA but not in those rabbits with normal PRA; P-113 also did not decrease arterial pressure in the chronic hypertensive dog unless sodium depletion was superimposed. In the conscious two-kidney dog, acute renal artery stenosis increased both arterial pressure and PRA within minutes, and P-113 blocked the rise in pressure associated with the increase in PRA. Therefore, although apparent species differences between the rabbit and the dog occur, the present data indicate that neither increased PRA nor excess salt retention is essential to the chronic maintenance of two-kidney hypertension in these two species; however, in the dog a role for angiotensin II in the acute phase is indicated.
D000305:Adrenal Cortex Hormones / Q000097:blood; D000804:Angiotensin II / Q000097:blood; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D001806:Blood Urea Nitrogen; D004195:Disease Models, Animal; D004285:Dogs; D005260:Female; D006977:Hypertension, Renal / Q000097:blood / Q000503:physiopathology*; D008297:Male; D008722:Methods; D011188:Potassium / Q000097:blood; D011817:Rabbits; D012078:Renal Artery Obstruction / Q000097:blood / Q000503:physiopathology*; D012083:Renin / Q000097:blood; D012504:Saralasin / Q000008:administration & dosage; D012964:Sodium / Q000097:blood
D000305:Adrenal Cortex Hormones; D000804:Angiotensin II; D012964:Sodium; D012083:Renin; D012504:Saralasin; D011188:Potassium