Cytochrome P-450-4A1 (CYP4A1) is an omega-hydroxylase that catalyzes the metabolism of arachidonic acid to 20-hydroxyeicosatetraenoic acid (20-HETE). The goal of this study was to determine the vasomotor consequences of vascular overexpression of CYP4A1. Isolated rat gracilis muscle arterioles transfected ex vivo with an expression plasmid containing CYP4A1 cDNA expressed more CYP4A protein tha...

The objectives of this study were to determine whether placental growth factor (PlGF) exerts a vasodilatory effect on rat uterine vessels (arcuate arteries and veins) and to examine regional differences in reactivity by comparing these responses to those of comparably sized mesenteric vessels. We also sought to examine and compare its effects on human uterine and subcutaneous vessels. All vesse...

When exposed to an increasing transmural pressure, middle cerebral arteries of the cat exhibit reduction of internal diameter which is mediated by vascular muscle cell depolarization. This laboratory has recently demonstrated that this "pressure-induced" activation is dependent upon the presence of an intact endothelium. The present studies were undertaken to determine if this phenomenon is due...

Hydroforging is a hybrid forming operation whereby a thick tube is formed to a desired geometry by combining forging and hydroforming principles. Through this process hollow structures with high strength-to-weight ratio can be produced for applications in power transmission systems and other structural components that demands high strength-to-weight ratio. In this process, a thick tube is defor...

Gokina, Natalia I., and George Osol. Temperature and protein kinase C modulate myofilament Ca21 sensitivity in pressurized rat cerebral arteries. Am. J. Physiol. 274 (Heart Circ. Physiol. 43): H1920–H1927, 1998.—The effects of pharmacological activation and inhibition of protein kinase C (PKC) and temperature on the relationship between cytoplasmic Ca21 and lumen diameter were studied in pressu...

Endothelium-derived hyperpolarizing factor (EDHF) plays an important role in the regulation of vascular microcirculatory tone. This study explores the role of estrogen in controlling EDHF-mediated vasodilation of uterine resistance arteries of the rat and also analyzes the contribution of endothelial cell (EC) Ca(2+) signaling to this process. A parallel study was also performed with mesenteric...

Tortuous arteries are often associated with aging, hypertension, atherosclerosis, and degenerative vascular diseases, but the mechanisms are poorly understood. Our recent theoretical analysis suggested that mechanical instability (buckling) may lead to tortuous blood vessels. The objectives of this study were to determine the critical pressure of artery buckling and the effects of elastin degra...

Previous in vivo studies have shown that vasopressin, which releases the endothelium-derived relaxing factor and constricts coronary smooth muscle, produces augmented constriction of coronary microvessels perfused by mature collaterals. We hypothesized that chronic perfusion through collaterals produces endothelial dysfunction in the recipient vasculature. Mature collaterals were stimulated in ...

This study compared the effect of lung congestion with and without left heart (LH) distension on breathing frequency (fr) and discriminated among responses mediated by myelinated and nonmyelinated vagal afferents. Cardiopulmonary bypass perfusion of anesthetized dogs was used to isolate reflexes. The following three groups were prepared: 1) lung vessels pressurized by pumping into the main pulm...