Renoprotection by Telmisartan versus Benazepril in Streptozotocin Induced Diabetic Nephropathy

Diabetic nephropathy (DN) is one of the major causes of end stage renal disease. Angiotensin converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARB) are preferred for delaying progression of DN. This study compared the preventive renal effects of telmisartan (10 mg/kg, p.o.), an ARB, that completely blocks angiotensin action, and benazepril (5 mg/kg, p.o.), an ACE inhibitor, which is a partial blocker of angiotensin II production, in an animal model of diabetic nephropathy. DN was induced by streptozotocin (50 mg/kg, i.p.) single injection in male albino rats. Biochemical parameters (creatinine clearance, urinary protein and blood urea) were significantly (p<0.01) altered in diabetic rats after 4 weeks. Telmisartan (10 mg/kg, p.o.) and benazepril (5 mg/kg, p.o.) treatment significantly (p<0.01) reduced elevated levels of blood urea and urinary protein in diabetic rats. After 8 weeks of diabetes there was significant difference in reduction of blood urea in between telmisartan and benazeril group. Difference between telmisartan and benazepril for reduction in proteinuria was not singnificant. Difference between telmisartan and benazepril for creatinine clearance improvement was also not significant (p>0.05). Histology revealed beneficial effects produced by both drugs. This study demonstrates telmisartan is equally renoprotective as benazepril.