The excretion of renal cells following necrosis of the proximal convoluted tubule.

Abstract

THE number of substances known to cause renal damage is increasing year by year. Phenacetin and aspirin, are 2 useful analgesic compounds which have fallen under suspicion although the evidence implicating them is largely circumstantial. (Leading Article, 1965). A technique that has been used to assess possible nephrotoxicity is to measure the rate of renal cell excretion in human volunteers taking the suspected drug (Harvald, Valdorf-Hansen and Nielsen, 1960; Harvald and Clausen. 1960; Clausen and Harvald, 1961; Scott, Denman and Dorling, 1963; Prescott. 1965, 1966). Both aspirin. and. in some cases phenacetin, have been found to cause a large increase in the number of renal tubular cells excreted in the urine, suggesting that these and other constituents of analgesic mixtures may be nephrotoxic. These observations were made on human subjects and the cell excretion rates were not correlated with the histological appearance of the kidneys. In consequence the interpretation of renal cell excretion rates in terms of renal damage is impossible. The purpose of the present experiment was to see how far alterations in renal cell excretion could be correlated with changes in renal histology after giving a well recognised nephrotoxin. The agent chosen was mercuric chloride. which produces a selective necrosis of the proximal convoluted tubules. In addition to studying the cell excretion and renal histology we have also used the occurrence of glycosuria as a simple measure of proximal tubular dysfunction.