Renin content in subcellular fractions of kidney extract of renovascular hypertensive rats.

SUARY Renovascular hypertension was produced in Wistar-King strain female rats by left renal artery clipping. The clipped kidney and the contralateral untouched kidney were cut into cortical, cortico-medullary and medullary portion. The cortical extract was divided into subcellular fractions by the step-wise centrifugation method. Enzyme activity of acid phosphatase, cytochrome C oxidase and glucose-6-phosphatase was determined to ascertain the nomenclature of each fraction. Renin content in these fractions was determined by bioassay and it was expressed as equivalent activity of angiotensin II per mg of tissue protein. Renin content in whole kidney extract of the clipped kidney was 2 times higher than that in the normal kidney described in our previous report. Cortex had also high renin content and it was 2 times higher than in the normal kidney, while medulla did not show any renin activity as well as that in the normal kidney. The renin content was highest in lysosomal fraction, which was 4 times greater than that in the normal kidney. Mitochondrial, mitochondrial-microsomal or soluble fraction had also higher renin content than respective fraction in the normal kidney. No renin activity was found in microsomal fraction as well as in that fraction in the normal kidney. In the contralateral untouched kidney, renin activity could not be demonstrated in any of the extracts or subcellular fractions.