Sequential studies on the pathophysiology of glycerol-induced acute renal failure

The role of volume depletion and renal ischemia in the development of renal functional impairment in glycerol-induced ARF is not clear. This study was designed to evaluate the role of volume depletion in this model by determining the hemodynamic and functional alterations which occur between 3 and 18 hr after glycerol administration and the reversibility of these changes in response to Ringer loading. Three hours after glycerol, Cln and RBF, measured by flowmeter, were reduced 70% and 52%, respectively, in comparison with control values. FeNa was 0.04%. Ringer loading increased Clkn to 103% and RBF to 93% of control values. Qualitatively similar results were found 6 hr after glycerol. At 18 hr, Cln and RBF were 47% of control values. After Ringer loading, RBF rose to 100% of control. The response of Cln, however, was a function of the baseline FeNa. Cln incrased substantijally in rats with low FeNa but changed only slightly in animals in which this parameter was increased. These studies indicate that the early reduction in the Cln is dependent upon the fall in RBF. At 12 and 18 hr, however, the fall in Cln is not blood flow-dependent, and a second mechanism must be operative. FeNa seems to be a reliable index of the functional status of a given animal.