Effect of captopril on chronic puromycin aminonucleoside nephrosis in rats

The effect of captopril, an angiotensin converting enzyme inhibitor, on the progression of chronic puromycin aminonucleoside (PAN) nephrosis was examined. Rats were injected with 15 mg/100 gm body weight PAN and 5 mg/100 gm body weight, on weeks - 1 and 5, respectively. A third group was injected with an equivalent volume of 0.9% saline, intraperitoneally (Group III) on week - 1 and 5. Beginning week 0, group I received 50 mg/kg captopril daily in the drinking water for 12 weeks. Group II received no treatment. Captopril failed to attenuate the peak level of proteinuria induced by the first injection of PAN or to alter the rate of decline of proteinuria when begun 1 week after the PAN injection. However, captopril did blunt the increase in urinary protein excretion following the second injection of PAN (p less than 0.05). Group II became hypertensive compared to Group I on week 8 and 12 and Group III on week 12 (p less than 0.05). Group I and II could not be distinguished on the basis of renal histologic rank (p = 0.80). We conclude that captopril affords some protection against the development of PAN-induced proteinuria, but it does not accelerate the recovery phase when glomerular permselectivity is being regained.