The control of the local supply of oxygen to a skeletal muscle vascular bed was analyzed by: (1) determining if a relative oxygen lack causes vascular dilation, (2) ascertaining the vascular elements responsible for the dilation, and (3) attempting to elucidate the mechanism of the dilation. When the concentration of oxygen in the inspiratory air was reduced from that in room air to 18% without...

As obese Zucker rats (OZR) manifesting the metabolic syndrome exhibit enhanced vascular adrenergic constriction and potentially an enhanced adrenergic activity vs. lean Zucker rats (LZR), this study tested the hypothesis that OZR exhibit an improved tolerance to progressive hemorrhage. Preliminary experiments indicated that, corrected for body mass, total blood volume was reduced in OZR vs. LZR...

UNLABELLED Extracorporeal Shock Wave Therapy (ESWT) is a golden standard for treatment of kidney and urinary calculi. It is also widely used in a number of orthopedic pathologies and other fields of medicine. Although clinical success the exact mechanism of shock wave technology is not well established. Cremaster muscle model used in our experiment is structurally and functionally similar to ot...

The vasodilator effect of local hypercapnic acidosis, produced by intra-arterial infusion of an acid buffer solution consisting of a mixture of glycine and hydrochloric acid, in the perfused hind limb and in the perfused gastrocnemius muscle of anesthetized dogs was examined at normal plasma calcium concentration and during elevation of the plasma calcium concentration produced by intra-arteria...

Sphingosine-1-phosphate (S1P) participates in inflammation; however, its role in leukocyte rolling is still unclear. Here we use intravital microscopy in inflamed mouse cremaster muscle venules and human endothelial cells to show that S1P contributes to P-selectin-dependent leukocyte rolling through endothelial S1P receptor 3 (S1P3) and Gαq, PLCβ and Ca(2+). Intra-arterial S1P administration in...

A null mutation was prepared in the mouse for CD18, the beta2 subunit of leukocyte integrins. Homozygous CD18 null mice develop chronic dermatitis with extensive facial and submandibular erosions. The phenotype includes elevated neutrophil counts, increased immunoglobulin levels, lymphadenopathy, splenomegaly, and abundant plasma cells in skin, lymph nodes, gut, and kidney. Very few neutrophils...

UNLABELLED Obesity is related to insulin resistance and hypertension, but the underlying mechanisms are unclear. Insulin exerts both vasodilator and vasoconstrictor effects on muscle resistance arteries, which may be differentially impaired in obesity. OBJECTIVES To investigate whether vasodilator and vasoconstrictor effects of insulin are impaired in muscle resistance arteries of obese rats ...

To determine the skeletal muscle stimulation parameters that are most important in establishing vasodilation in the microvasculature, I tested whether arteriolar diameter during 2 min of repetitive, short-duration, tetanic skeletal muscle contractions increased with changes in stimulus frequency, stimulation train duration, and contraction frequency. To test this, the diameter of transverse art...

Previous studies on mice have revealed that the Griffonia simplicifolia I (GSI) lectin selectively binds to capillaries in a number of microvascular beds. These observations suggest that the lectin might be a suitable microvascular marker for physiological studies of skeletal muscle, particularly when fluorescent visualization of vessels is desired independently of their perfusion status. Since...

How vessels become leaky he cremaster, an obscure muscle that keeps testicles close to the male body when cold sets in, has had two moments of glory. The more recent was at New York's Guggenheim museum in 2003, when Matthew Barney presented his full cycle of Cremaster films and associated paraphernalia. There were few if any participants in that artfest who were aware of the cremaster's earlier...