Type II diabetes abrogates sex differences in endothelial function in premenopausal women

Obesity is a more potent cardiovascular risk factor (CVRF) in men than in women. Because traditional CVRFs cannot fully account for this sex difference, we tested the hypothesis that compared with men, women exhibit more robust endothelial function independent of obesity and that this sex difference is abrogated by diabetes. We studied leg blood flow (LBF) responses to graded intrafemoral artery infusions of the endothelium-dependent vasodilator methacholine chloride (Mch) and the endothelium-independent vasodilator sodium nitroprusside (SNP) in groups of lean, obese (OB), and type II diabetic (DM) premenopausal women and age- and body mass index-matched men. LBF response to intrafemoral administration of L-NMMA, an inhibitor of nitric oxide synthase, was also assessed in normal men and women. Maximum LBF increments in response to Mch were 347+/-57% versus 231+/-22% in lean women versus men (P