AIMS Caveolin-1 (Cav-1) interacts with large conductance Ca(2+)-activated potassium channels (BKCa) and likely exerts a negative regulatory effect on the channel activity. We investigated the role of Cav-1 in modulating BK(Ca) channel-mediated, endothelium-derived hyperpolarizing factor (EDHF)-dependent arteriolar dilation in normal condition and in an experimental model of obesity. METHODS A...

OBJECTIVES Little is known about the relation of pubertal development on endothelial function and arterial elasticity in children and adolescents; therefore, we compared brachial artery flow-mediated dilation and carotid artery elasticity across Tanner (pubertal) stages in children and adolescents. STUDY DESIGN Blood pressure, fasting lipids, glucose and insulin, body fat, insulin sensitivity...

The effects of removal of endothelium and changes in blood flow in conscious dogs on the responses of large iliac artery diameter to local infusion of nitroglycerin, acetylcholine, epinephrine, and norepinephrine into the iliac artery were studied. Infusion of agonists did not change mean arterial pressure or heart rate. In vessels with intact endothelium, iliac diameter increased with nitrogly...

Although episodic changes in shear stress have been proposed as the mechanism responsible for the effects of exercise training on the vasculature, this hypothesis has not been directly addressed in humans. We examined brachial artery flow-mediated dilation, an index of NO-mediated endothelial function, in healthy men in response to an acute bout of handgrip exercise and across an 8-week period ...

OBJECTIVE Elevated levels of C-reactive protein (CRP), a proinflammatory marker, are associated with reduced systemic endothelium-dependent NO-mediated dilation in patients with coronary artery disease; however, the direct effect of CRP on coronary microvascular reactivity remains unknown. Herein, we examined whether CRP can modulate endothelium-dependent NO-mediated dilation of coronary arteri...

One characteristic of hypertension is a decreased endothelium-dependent nitric oxide (NO)-mediated vasodilation; however, the underlying mechanism is complex. In endothelial cells (ECs), L-arginine is the substrate for both NO synthase (NOS) and arginase. Because arginase has recently been shown to modulate NO-mediated dilation of coronary arterioles by reducing l-arginine availability, we hypo...

AIMS Endothelial dysfunction in resistance arteries (RAs) leads to end-organ damage in type 2 diabetes. Remodelling of RAs in response to chronic increases in blood flow depends on the integrity of the endothelium. Since type 2 diabetes impairs endothelial sensitivity to flow and increases oxidative stress, we hypothesized that flow-induced remodelling in RAs would be impaired in diabetes. Thus...

BACKGROUND We previously demonstrated that coronary arteriolar dilation in response to acidosis is mediated by the opening of ATP-sensitive potassium (KATP) channels. However, the signal transduction involved in the KATP-channel activation during acidosis has not been elucidated. A recent study in cardiac myocytes implied that pertussis toxin (PTX)-sensitive G proteins may be involved in the si...

PURPOSE Elevated levels of C-reactive protein (CRP), a proinflammatory marker, are associated with systemic vascular disorders. In addition, clinical studies have implicated that elevated CRP is an independent risk factor for diabetic retinopathy and age-related macular degeneration. However, the direct effect of CRP on ocular microvascular reactivity remains unknown. The authors examined wheth...

BACKGROUND Adenosine triphosphate (ATP), a potent vascular regulator in the cerebral circulation, initiates conducted vasomotor responses which may be impaired after pathological insults. We analyzed the mechanism of ATP-induced local vasomotor responses and their effect on conducted vasomotor responses in rat cerebral penetrating arterioles. METHODS Arterioles were cannulated and their inter...