The use of ACE inhibitors on diabetic patients without renal disease

DOSE-DEPENDENT EFFECT OF CAPTOPRIL ON AORTIC REACTIVITY OF STREPTOZOTOCIN-DIABETIC RATS

Diabetes mellitus is a primary risk factor for cardiovascular disorders. Strategies that interrupt the renin-angiotensin system have been known to reduce cardiovascular disease. The present study was performed to investigate the effect of sub-chronic administration of captopril on the aortic reactivity of streptozotocin-diabetic rats. Streptozotocin-diabetic rats received captopril (30 and 50 mg/kg per day) for 2 months. Contractile responses to phenylephrine (PE) and relaxation responses to acetylcholine (ACh) and isosorbide dinitrate (ISD) were obtained from aortic rings. Concentration-response curves from captopril-treated diabetic rats to PE were attenuated compared with vehicle (Saline)-treated diabetic rats, especially at a dose of 50 mg/kg captopril. In addition, endothelium-dependent relaxation responses induced by ACh were significantly higher in captopril-treated diabetic rats compared with diabetic rats. The endothelium-independent relaxation responses for ISD were found not to be significantly different among the groups. Therefore, sub-chronic treatment of diabetic rats with captopril in a dose-dependent manner could prevent the functional changes in vascular reactivity in diabetic rats.

Protective effect of enalapril on vascular reactivity of the rat aorta

Cardiovascular complications are the major cause of morbidity and mortality in patients with diabetes mellitus (DM). Strategies that interrupt the renin-angiotensin system have been shown to reduce the ensuing threatening risk factors. The present study was carried out to investigate the effect of subchronic administration of enalapril on the aortic reactivity of streptozotocin (STZ)-diabetic rats. For this purpose, STZ-diabetic rats received enalapril (10 and 20 mg/kg ip) daily for 2 months. Contractile responses to phenylephrine (PE) and relaxation responses to acetylcholine (Ach) and isosorbide dinitrate (ISD) were obtained from aortic rings. Concentration-response curves from enalapril-treated diabetic (ED) rats to PE were attenuated as compared to vehicle-treated diabetics (VD), especially at a dose of 20 mg/kg for enalapril. In addition, endothelium-dependent relaxation responses induced by Ach was significantly higher in ED rats as compared to diabetic ones. The endothelium-independent relaxation responses for ISD were also found not to be significantly different among the groups. Therefore, subchronic treatment of diabetic rats with enalapril in a dose-dependent manner could prevent the functional changes in vascular reactivity in diabetic rats.