Hypertension is associated with endothelial dysfunction that is attributable to oxidative stress and a proinflammatory state. Under these conditions, enhanced expression of cyclooxygenase-2 might lead to increased production of vasoconstrictor prostanoids and reactive oxygen species that reduce the bioavailability of endothelium-derived nitric oxide. To investigate the contribution of cyclooxyg...

Vasoactive intestinal peptide (VIP) is known to induce histamine release in human skin and known to include a NO-dependent dilation in several other vascular beds. However, the relative contribution of histamine and NO to VIP-mediated vasodilation in human skin is unknown. Forty three subjects volunteered to participate in two studies designed to examine the mechanism of VIP-mediated vasodilati...

The objectives of this study were to determine if psychosocial stress impairs dilation through endothelium-derived relaxing factor (EDRF)-mediated mechanisms and if this effect is long lasting. Monkeys were fed an atherogenic diet for 36 mo while in one of three experimental conditions: (a) stable social groups ("unstressed," n = 6); (b) unstable social groups for the first half of the experime...

AIMS To bridge the beneficial metabolic effects of pronounced weight loss on one side and the data on morbidity and mortality on the other side, we investigated the impact of profound weight loss on structural and functional markers of early atherosclerosis. METHODS AND RESULTS Thirty-seven obese adults were examined before and 18 months after bariatric surgery. Carotid intima-media thickness...

To test the hypothesis that protein kinase C (PKC)beta-induced reactive oxygen species (ROS) underlie the vascular dysfunction in diabetes, we examined the effects of (S)-13[(dimethylamino)-methyl]-10,11-14,15-tetrahydro-4,9:16,21-dimetheno-1H,13H-dibenzo[e,k]pyrrolo[3,4-h][1,4,13]oxadi-azacyclohexadecene-1,3(2H)-dione (LY333531; LY), a specific PKCbeta inhibitor, on arachidonic acid (AA)-media...

OBJECTIVE Mitochondrial dysfunction plays a key pathophysiological role in type 2 diabetes mellitus (T2DM). Data delineating relationships between mitochondrial and endothelial dysfunction in humans with T2DM are lacking. METHODS AND RESULTS In 122 human subjects (60 with T2DM, 62 without T2DM), we measured endothelial function by brachial artery ultrasound (flow mediated dilation) and digita...

The purpose of this study was to determine if six weeks of folic acid supplementation would improve brachial artery endothelial-dependent flow-mediated dilation in eumenorrheic female runners with previously normal serum folate levels. This was a prospective, double-blinded, randomized pilot study with convenience sampling. Sixteen eumenorrheic subjects who were not taking birth control pills a...

OBJECTIVE The effects of coronary perivascular adipose tissue (PVAT) on vasomotor tone are influenced by an obese phenotype and are distinct from other adipose tissue depots. The purpose of this investigation was to examine the effects of lean and obese coronary PVAT on end-effector mechanisms of coronary vasodilation and to identify potential factors involved. APPROACH AND RESULTS Hematoxyli...

This study examined the acute endothelial responses to an exercise bout in coronary artery disease (CAD) patients. Nineteen males with CAD (63 ± 8 years) were assessed at rest and 15 minutes following a submaximal exercise bout (recovery). Brachial artery endothelial-dependent function was assessed using flow-mediated dilation (FMD). Brachial artery diameters and velocities were measured using ...

OBJECTIVES The present study was designed to assess whether exercise training can enhance endothelium-dependent dilatation in healthy young men. BACKGROUND Exercise has been shown to reduce cardiovascular morbidity and mortality, but the mechanisms for this benefit are unclear. Endothelial dysfunction is an early event in atherogenesis, and animal studies have shown that exercise training can...