Increased plasma renin activity after peritoneal dialysis.

Abstract

An examination was made of the effects of changes in plasma sodium concentration and water balance during peritoneal dialysis on renin secretion. Plasma renin activity, plasma sodium concentration, plasma volume, and arterial blood pressure were measured in 14 patients with chronic renal failure (chronic glomerulonephritis) before and after peritoneal dialysis. The amount of water removed by peritoneal dialysis was also measured.The results were as follows: 1) Plasma renin activity was increased significantly after peritoneal dialysis. The average increase was 58.1±15.8 (S.E.)% of the initial value. 2) There was no significant correlation between the amount of water removed and plasma renin activity. 3) Mean arterial pressure rose slightly after peritoneal dialysis but not to a statistically significant degree. 4) Plasma sodium concentration was increased significantly after peritoneal dialysis. There was no significant inverse correlation between plasma sodium concentration and renin activity. There was also no significant inverse correlation between the increased plasma renin activity and changes in plasma sodium concentration. 5) The decrease in plasma volume after peritoneal dialysis was significant. There was a significant correlation between the increased renin activity and the decreased plasma volume.From the present study, we conclude that the dominant stimulus to renin secretion in peritoneal dialysis is a decrease in plasma volume.