BACKGROUND To determine the effects of high sucrose diets on vascular reactivity. We hypothesized that similar to high fat diets (HFD), HSD feeding would lead to increased adiposity resulting in inflammation and oxidative stress-mediated impairment of vasodilation. METHODS Male Sprague-Dawley rats were fed control chow (Chow), HSD or HFD diets for 6 weeks. The role of inflammation and oxidati...

Blood flow increases to exercising skeletal muscle, and this increase is driven primarily by vasodilation in the contracting muscles. When oxygen delivery to the contracting muscles is altered by changes in arterial oxygen content, the magnitude of the vasodilator response to exercise changes. It is augmented during hypoxia and blunted during hyperoxia. Because the magnitude of the increased va...

The relative contribution of endothelial vasodilating factors to acetylcholine (ACh)-mediated vasodilation in the forearm cutaneous microcirculation is unclear. The aims of this study were to investigate the contributions of prostanoids and cutaneous C fibers to basal cutaneous blood flow (CuBF) and ACh-mediated vasodilation. ACh was iontophoresed into the forearm, and cutaneous perfusion was m...

The adenosine agonist 5-( N-ethylcarboxamido)adenosine (NECA) induces vasodilation in the pulmonary circulation via A2-adenosine-receptor activation. We addressed whether prolonged treatment with NECA desensitizes in A2-adenosine- receptor function in isolated lung and pulmonary artery smooth muscle cells (PASMC). In lung microcirculation preconstricted with a hypoxic gas, initial administratio...

Local vasodilation in response to hypoxia is a fundamental physiologic response ensuring oxygen delivery to tissues under metabolic stress. Recent studies identify a role for the red blood cell (RBC), with hemoglobin the hypoxic sensor. Herein, we investigate the mechanisms regulating this process and explore the relative roles of adenosine triphosphate, S-nitrosohemoglobin, and nitrite as effe...

OBJECTIVE Data from experimental studies have suggested that the increased formation of advanced glycation end products (AGEs) is one of the causes of endothelial dysfunction in diabetes. This study was performed to investigate whether changes in endothelium-dependent vasodilation, a marker of endothelial function, were related to serum AGEs concentrations in patients with type 2 diabetes. RE...

Although insulin-mediated vasodilation is impaired in insulin resistance, the mechanisms of this are unknown. We investigated factors mediating vasoactive responses to insulin in control and insulin-resistant rats. Responses to insulin in small mesenteric arteries from control and insulin-resistant rats were investigated after blocking endothelin-A receptors, cyclooxygenase, nitric oxide syntha...

Vasodilation profiles following a short-term infusion of nitric oxide (NO), acetylcholine (ACh), and sodium nitroprusside (SNP) into an isolated perfused mesenteric artery bed were analyzed in rats to examine their vasodilatory efficacy under physiological conditions. These compounds commonly increase the intracellular NO concentration to exert vasodilatory activity. In an experiment with exoge...

Ikezaki, Hiroyuki, Manisha Patel, Hayat Önyüksel, Syed R. Akhter, Xiao-pei Gao, and Israel Rubinstein. Exogenous calmodulin potentiates vasodilation elicited by phospholipid-associated VIP in vivo. Am. J. Physiol. 276 (Regulatory Integrative Comp. Physiol. 45): R1359–R1365, 1999.—The purpose of this study was to determine whether exogenous calmodulin potentiates vasoactive intestinal peptide (V...

I have presented data to support an interaction of insulin with the vascular endothelium to cause the release of NO and vasodilation. In effect, insulin-mediated vasodilation can be viewed as a novel test of endothelial function. The physiologic significance of insulin-mediated, endothelium-dependent vasodilation is not fully understood, but some insight has been gained. Insulin-mediated vasodi...