Effects of Preliminary Renal Ischemia on Experimental Renal Hypertension

Abstract

The effects of preliminary renal ischemia produced by bilateral renal artery occlusion for 2, 4, 4.5, 5, and 6 hrs. on subsequent exptl. renal hypertension production in the dog were studied. Results show that severe renal damage has an effect on the pattern of hypertension development after bilateral renal artery constriction. Some dogs survive a temporary bilateral renal artery occlusion for 4 or more hrs. with the development of severe renal damage and insufficiency as indicated by renal function studies, including the use of renal clearance and saturation techniques, and pathologic studies. Correlation exists between the ratio of Cpah/TMpah and the mean femoral arterial pressure following bilateral renal artery constriction. Dogs survive a period of renal ischemia, produced by a 4-hr. bilateral renal artery occlusion, with regularity. The degree of damage induced by 2, 4, 4.5, 5, and 6 hrs. is extremely variable. The typical pathologic findings in kidneys following bilateral renal artery occlusion is one of a patchy type of tubular degeneration, associated areas of increased interstitial tissue. There is no localization of the renal damage to any particular part of the nephron.