The effect of streptozotocin-induced diabetes and insulin treatment on angiotensin converting enzyme activity.

Diabetes mellitus is associated with an increased incidence of hypertension and renal failure. Alterations in the renin-angiotensin system may contribute to the development of cardiovascular disorders in diabetics. This study examined diabetic associated changes in angiotensin converting enzyme (ACE). ACE activity was measured in serum, lung and kidney tissue derived from normoglycemic or 3-48 day streptozotocin (STZ)-induced diabetic rats. Serum and tissue ACE activity were not altered 3 days post STZ treatment. Serum ACE activity significantly increased in the diabetic group relative to controls, beginning 12 days post STZ treatment. Insulin treatment for 10 days partially normalized serum ACE activity. Therefore, STZ-induced diabetes produced significant changes in ACE activity that are partially corrected by insulin treatment.