Conjugate effects of saralasin and indomethacin on kidney function in anesthetized dog

The intravenous administration of the cyclooxigenase blocking indomethacin results in a very rapid and sharp decrease of renal blood flow (RBF) and in a decrease of water and sodium excretion in anesthetized dogs. The result is very similar to that of the angiotensin II infusion. The present study was undertaken to examine in anesthetized dogs, how the angiotensin II receptor antagonist saralasin can influence the kidney function and the renal effects of the intravenously administered indomethacin. 0.2 micrograms/kg/min saralasin infused directly into the left renal artery induced a slight drop in the arterial blood pressure, and a slight but significant decrease in the renal vascular resistance without affecting other renal parameters. The intrarenal infusion of saralasin, when it preceded the administration of indomethacin, almost completely abolished the renal hemodynamic effects of indomethacin and decreased its effect on the renal water and sodium excretion. It seems therefore probable that in anesthetized dogs the renin-angiotensin system may play a role in the development of the renal effects of indomethacin.