Mechanisms of Autoregulation in Isolated Perfused Kidney.

Abstract

Experiments were performed on the isolated pump-lung perfused kidney of the dog. Calculations of "intrarenal" vascular resistance (renal artery pressure-tissue pressure/flow) were made in blood and dextran perfused kidneys in order to distinguish between the relative influences of tissue pressure and post-glomerular viscosity changes on "overall" (RA-RV/Flow) resistance. The relative vascular "clamping" effects of Bowman capsule extravascular pressure and general tissue pressure were also evaluated. Date suggest that as the renal artery pressure is elevated, blood flow regulation is brought about by (a) the combined effects of increased tissue pressure and Bowman capsule extravascular pressure, and (b) increases in post-glomerular viscosity resulting from glomerular filtration.