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) inhibitor and angiotensin receptor blocker (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 is 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. Significant (p<0.05) difference for reduction in blood urea was present between telmisartan and benazepril after 8 weeks of diabetes. 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.