Excess dietary sodium has been linked to the development of hypertension and other cardiovascular diseases. In humans, effects consumption on endothelial function have not separated from blood pressure. The present study was designed determine if intake affected endothelium-dependent dilation (EDD) independently changes in pressure.Fourteen healthy salt-resistant adults were studied (9M, 5F; age 33 ± 2.4 years) a controlled feeding study. After baseline run-in diet, participants randomized...

Hyperandrogenism and vascular dysfunction often coexist in women with polycystic ovary syndrome (PCOS). We hypothesized that testosterone compromises cutaneous microvascular dilation PCOS via the endothelin-1 ET-B subtype receptor. To control isolate testosterone's effects on dilation, we administered a gonadotropin-releasing hormone antagonist (GnRHant) for 11 days obese, otherwise healthy [controls, 22.0 (4) yr, 36.0 (3.2) kg/m(2)] or [23 35.4 (1.3) kg/m(2)], adding (T; 2.5 mg/day) 8-11....

Previous studies have demonstrated an inverse relation between resting muscle sympathetic nerve activity (MSNA) and vasoconstrictor responsiveness (i.e., transduction), such that those with high MSNA low vascular responsiveness, vice versa. The purpose of this investigation was to determine whether biological sex influences the balance beat-to-beat transduction. We measured blood pressure (BP) during supine rest in 54 healthy young adults (27 females: 23 ± 4 yr, 107 8/63 8 mmHg; 27 males: 25...

Elevated NaCl concentrations of the cerebrospinal fluid increase sympathetic nerve activity (SNA) in salt-sensitive hypertension. Neurons rostral ventrolateral medulla (RVLM) play a pivotal role regulation SNA and receive mono- or polysynaptic inputs from several hypothalamic structures responsive to hypernatremia. Therefore, present study investigated contribution RVLM neurons pressor response Lateral ventricle infusion 0.15 mol/L, 0.6 1.0 mol/L (5 µL/10 minutes) produced...

Endothelin-1 (ET-1) contributes to age-related endothelial dysfunction in men via the ETA receptor. However, there are sex differences ET-1 system, and ETB receptors modulated by hormones. The purpose of this study was test hypothesis that contribute impaired vasodilatory function postmenopausal women (PMW). We measured flow-mediated dilation (FMD) using ultrasound, cutaneous nitric oxide-mediated vasodilation during local heating (42°C) laser Doppler flowmetry 18 young (YW; 22 ± 1 yr) 16...

The American Heart Association recommends no more than 1500 mg of sodium/day as ideal. Some cohort studies suggest low-sodium intake is associated with increased cardiovascular mortality. Extremely diets (≤500 mg/d) elicit activation the renin-angiotensin-aldosterone system and stimulate sympathetic outflow. effects an Association-recommended diet on regulation vasculature are unclear. Therefore, we assessed whether a 1000 mg/d alters outflow vascular transduction compared commonly...

Postmenopausal women (PMW) display exaggerated increases in blood pressure (BP) during exercise, yet the mechanism(s) involved remain unclear. Moreover, research on impact of menopausal changes estradiol cardiovascular control exercise are limited. Herein, we tested hypothesis that sympathetic responses augmented PMWcompared with young (YW), and administration attenuates these responses.Muscle nerve activity (MSNA) mean arterial (MAP) were measured 13 PMW (58 ± 1 yr) 17 YW (22 2 min...

The endothelin-B receptor (ET B R) mediates vasodilation in young women, an effect that is absent postmenopausal women. We have previously demonstrated ET R-mediated regulated by estradiol (E 2 ) women; however, the impact of E on R function women remains unknown. Accordingly, objective this study was to test hypothesis exposure restores dilation Ten healthy (55 ± years age, 5 3 since menopause) completed study. administered transdermal patch for 7 days (0.1 mg/day, Vivelle-Dot patch)....

Low testosterone in middle-aged/older men contributes to accelerated vascular aging, including endothelial dysfunction. However, the mechanisms by which low affects dysfunction are not well understood. We sought determine whether higher endothelin-1 (ET-1) levels associated with reduced brachial artery flow-mediated dilation (FMD) testosterone. Plasma ET-1 was quantified 60 categorized as young (n = 20, age 30 ± 4 yr, 510 63 ng/dL), normal 59 6 512 115 or 8 265 47 ng/dL). Endothelial...

Increased arterial wave reflections can increase left ventricular wasted pressure effort (WPE) and cardiovascular disease risk. Naturally menstruating women experience fluctuations in sex hormones with known cardioprotective effects. We sought to determine whether hormonal alter hemodynamics or reflections, thereby WPE, contribute differences. hypothesized that premenopausal would have favorable reflection changes reduced WPE during high- vs. low-hormone cycle phases compared men. tested 13...

Increased dietary sodium is linked to hypertension, but most young adults display "sodium-resistant" blood pressure (BP), meaning BP not elevated with loading. In sodium-resistant rodents, fructose induces salt-sensitive via increased renal reabsorption. Therefore, we tested the impact of and on handling in healthy adults, hypothesizing that their combination would impair excretion increase BP. Thirty-six participants enrolled a randomized, double-blind, crossover trial involving three diets...

<h3>Background</h3> Left ventricular (LV) reverse remodelling after valve replacement in aortic stenosis (AS) has been classically linked to the hydraulic performance of device, but myocardial status at time surgery received little attention. <h3>Objective</h3> To establish predictors LV mass (LVM) regression 1 year a surgical cohort patients with AS based on preoperative clinical and echocardiographic parameters gene expression profile surgery. <h3>Methods</h3> Transcript levels...

Endothelin-1 (ET-1) contributes to declines in endothelial function postmenopausal women. To our knowledge, we show for the first time that aerobic exercise reduces ET-1-mediated vasoconstriction previously sedentary Moreover, improved endothelial-dependent dilation due part reductions vasoconstriction.

The purpose of this study was to examine the relationship between osmolality and efferent sympathetic outflow in humans. We hypothesized that increased plasma would be associated with increases directly measured outflow. Muscle successfully recorded eight healthy subjects during a 60-min intravenous hypertonic saline infusion (HSI; 3% NaCl) on one day isotonic (ISO) (0.9% different day. HSI provides an osmotic volume stimulus, whereas ISO volume-only stimulus. nerve activity quantified using...

Endothelin-1 is elevated in women with polycystic ovary syndrome (PCOS), and may play a role the endothelial dysfunction associated PCOS. binds two receptor subtypes, endothelin A (ET-A) B (ET-B). We hypothesized that ET-A mediates vasoconstriction cutaneous microvasculature without further while ET-B receptors mediate vasodilatation both groups of women, this response would be blunted During local skin warming, we used laser Doppler flowmetry combined intradermal microdialysis to measure...

Women are more susceptible to orthostatic intolerance. Peripheral α-adrenergic responsiveness is important in orthostasis and lower women compared men, modulated by female sex hormones. We tested the hypothesis that oestradiol attenuates peripheral cutaneous adrenergic responses with low tolerance (LT), whereas progesterone enhances high (HT). After completing a maximal body negative pressure test determine level of (cumulative stress index, CSI), self administered gonadotropin releasing...

The impact of 17β-oestradiol (E2) exposure on autonomic control orthostasis in young women is unclear. We tested the hypothesis that cardiovascular regulation more sensitive to E2 with low orthostatic tolerance. Women underwent an initial maximal lower body negative pressure (LBNP) test place them into a (LT, n = 7, 22 ± 1 years old, mass index kg m(-2)) or high tolerance group (HT, 24 m(-2)). then suppressed endogenous reproductive hormone production using gonadotrophin-releasing antagonist...

Young adults with a family history of hypertension (+FH) have increased risk developing hypertension. Furthermore, the blood pressure (BP) response to sympathoexcitatory stimuli in young can predict future development Therefore, we hypothesized women +FH would exaggerated cardiovascular and sympathetic reactivity compared without (-FH). Beat-by-beat mean arterial (MAP) muscle nerve activity (MSNA) were measured 14 (22 ± 1 yr, 21 kg/m(2), MAP 80 2 mmHg) 15 -FH 22 78 during acute maneuvers:...

The purpose of this study was to determine if plasma osmolality alters baroreflex control sympathetic activity when controlling for a change in intravascular volume; we hypothesized that would be greater during hyperosmotic stimulus compared with an isoosmotic volume expansion matched. Seven healthy subjects (25 +/- 2 yr) completed two intravenous infusions: hypertonic saline infusion (HSI; 3% NaCl) and, on separate occasion, isotonic (ISO; 0.9% NaCl), both at rate 0.15 ml x kg(-1) min(-1)....

Although dose-response curves are commonly used to describe in vivo cutaneous α-adrenergic responses, modeling parameters and analyses methods not consistent across studies. The goal of the present investigation was compare three analysis for vasoconstriction studies using one reference data set. Eight women (22 ± 1 yr, 24 kg/m(2)) were instrumented with microdialysis probes progressive norepinephrine (NE) infusions (1 × 10(-8), 10(-6), 10(-5), 10(-4), 10(-3) logM). NE infused alone,...