It has been reported that blockage of the renin–angiotensin system slows the progression to DN in patients with type 1 diabetes.[13] Some recent studies have also demonstrated the renoprotective effect of the angiotensin II receptor antagonist, irbesartan, in hypertensive patients.[14] The results of the present study indicate that irbesartan is beneficial in preventing experimental DN in rats, which excreted a large amount of protein in their urine. Here, REN is linked to type 1 diabetes mellitus.