Intrarenal Hemodynamics in Glycerol-Induced Myohemoglobinuric Acute Renal Failure in the Rat

Abstract

A modified 138 Xe washout technique was used to study changes in intrarenal hemodynamics during glycerol-induced acute renal failure in the rat. Within 10 minutes after glycerol injection, the flow fraction supplied to component 1 of the washout curve ("cortex A") decreases, reaching minimum values 24 hours afer glycerol (31% of control conditions). Seven days thereafter five of the rats, still uremic, showed cortical flow fractions less than 50% of control values. Nine others had recovered. Twenty-four hours after glycerol, renal blood flow was 27% and increased to 86% of control conditions in the recovered rats 7 days after glycerol. 85 Kr autoradiographs and silicone rubber casts of the renal vasculature demonstrated a severe cortical hypoperfusion at the height of oliguria that gradually disappeared in parallel with the functional recovery of the kidney. These observations, in good agreement with micropuncture data, suggest that oliguria and renal insufficiency in this experimental model are the result of a primary decrease in glomerular filtration rate due to an increased preglomerular resistance.