Background—Supraspinal sympathetic control of leg vascular tone is lost in spinal cord–injured individuals, but this does not result in a reduced leg vascular tone: Leg vascular resistance is even increased. The aim of this study was to assess the -adrenergic contribution to the increased vascular tone in the lower extremity in patients without central sympathetic control of leg circulation. Me...

BACKGROUND Sex hormones are known to affect cholesterol levels and vascular tone in women. The effects of testosterone on cholesterol and vascular tone in men are less well understood. Low testosterone levels have been associated with higher cholesterol levels in epidemiologic studies, but testosterone replacement has resulted in variable changes in cholesterol levels. Similarly, clinical studi...

AIMS As cardiovascular disease is characterized by reduced nitric oxide bioavailability, our aim was to determine the impact of this change on the mechanism underlying vascular tone of pressurized arteries in vitro and in vivo. METHODS AND RESULTS We used pressurized cerebral and mesenteric arteries in vitro and skeletal muscle arterioles in vivo to study the contribution of L-type (1 µmol/L ...

There is increasing evidence suggesting that epoxyeicosatrienoic acids (EETs) play an important role in cardioprotective mechanisms. These include regulating vascular tone, modulating inflammatory responses, improving cardiomyocyte function and reducing ischaemic damage, resulting in attenuation of animal models of cardiovascular risk factors. This review discusses the current knowledge on the ...

Purinergic control of vascular tone in the CNS has been largely unexplored. This study examines the contribution of endogenous extracellular ATP, acting on vascular smooth muscle cells, in controlling vascular tone in the in vivo rat retina. Retinal vessels were labelled by i.v. injection of a fluorescent dye and imaged with scanning laser confocal microscopy. The diameters of primary arteriole...

The capillary filtration coefficient (CFC) is assumed to reflect both microvascular hydraulic conductivity and the number of perfused capillaries at a given moment (precapillary sphincter activity). Estimation of hydraulic conductivity in vivo with the CFC method has therefore been performed under conditions of unchanged vascular tone and metabolic influence. There are studies, however, that di...

Disa Conference), edited by DJ Cockrell. Leicester, England, Leicester University Press, 1972, pp 298-304 9. Clark A: Thin film gauges for fluctuating velocity measurements in blood. J Sci Instrum 7: 548-556, 1974 10. Ling SC, Atabek HB, Fry DL, Patel DJ, Janicki JS: Application of heated-film velocity and shear probes to hemodynamic studies. Circ Res 23: 789-801, 1968 11. Yellin EL: Hydraulic ...

Pulmonary endothelial cells normally synthesize prostacyclin (PGI2) and nitric oxide (NO), which are both potent vasodilators. Although PGI2 is largely used to treat patients with severe pulmonary hypertension, its role in the physiology and pathophysiology of the pulmonary circulation is still debated. NO, which is now considered as the endogenous nitrovasodilator, is perhaps more involved tha...

The greater incidence of hypertension and coronary artery disease in men and postmenopausal women compared with premenopausal women has been related, in part, to gender differences in vascular tone and possible vascular protective effects of the female sex hormones estrogen and progesterone. However, vascular effects of the male sex hormone testosterone have also been suggested. Estrogen, proge...

Hypertension develops in most patients after transplantation when immunosuppression is based on cyclosporine and prednisone. The pathogenesis appears to be multifactorial but involves rapidly rising vasoconstrictor tone in renal and systemic vascular beds. Much of this tone reflects abnormal vascular function, characterized by impaired prostacyclin and EDRF effects, in conjunction with increase...