Primary Effects of Acute Oligocythemia on Renal Function

Abstract

Blood viscosity was reduced acutely by decreasing the erythro-cyte volume without changing total blood volume. Studies on 9 dogs indicated that this procedure had no effect on GFR, effective renal blood flow, urine flow, or the excretion of Na and K. Effective RPF was increased, with the resultant decrease in filtration fraction. Evidence is presented to show that the kidney adjusts to an acute reduction in blood viscosity by means of-constriction of the afferent arterioles. This serves to maintain a final constancy of effective renal blood flow and GFR.