Kinins contribute to the improvement of insulin sensitivity during treatment with angiotensin converting enzyme inhibitor

Abstract

Although angiotensin converting enzyme inhibitors and α1-blockers have been reported to improve insulin sensitivity, their mechanisms of action have not been elucidated. To investigate the role of kinins in insulin sensitivity, we treated 4-week-old spontaneously hypertensive rats with either an angiotensin converting enzyme inhibitor (enalapril), an α1- blocker (doxazosin), or an angiotensin II antagonist (losartan) for 3 weeks. A control group received no drugs. In addition, 18 rats treated with enalapril or doxazosin received a simultaneous administration of a kinin antagonist (Hoe 140). Glucose clamp testing was performed in each group. Enalapril (128 ± 1 mm Hg) and doxazosin (132±2 mm Hg) decreased mean blood pressure compared with control levels (148±1 mm Hg) (P