There is a paradoxical α-adrenoceptor-mediated coronary vasoconstriction whenever there is adrenergic activation of the heart, as during cardiovascular reflexes or exercise. A previous study demonstrated that this paradoxical vasoconstriction helps maintain blood flow to the vulnerable inner layer of the left ventricular wall during exercise, but the mechanism for this effect was not elucidated...

Hypertension is associated with an elevation in agonist-induced vasoconstriction, but mechanisms involved require further investigation. Many vasoconstrictors bind to phospholipase C-coupled receptors, leading to an elevation in inositol 1,4,5-trisphosphate (IP(3)) that activates sarcoplasmic reticulum IP(3) receptors. In cerebral artery myocytes, IP(3) receptors release sarcoplasmic reticulum ...

Naik, Jay S., Lusha Xiang, and Robert L. Hester. Enhanced role for RhoA-associated kinase in adrenergic-mediated vasoconstriction in gracilis arteries from obese Zucker rats. Am J Physiol Regul Integr Comp Physiol 290: R154–R161, 2006. First published September 1, 2005; doi:10.1152/ajpregu.00245.2005.—Obesity, insulin resistance, dyslipidemia, and hypertension are components of the pathophysiol...

In the accompanying article, we showed that AP5A displayed heterogenous vasoactive effects in rat resistance arteries. It induced a stable vasoconstriction in the superior epigastric artery (SEA) and a transient vasoconstriction in the mesenteric resistance artery (MrA). In the phenylephrine-precontracted MrA AP5A induced a marked vasorelaxation. In this study the noncompetitive inhibition of t...

CONTEXT Clinical observations and case reports suggest that there are important cerebrovascular complications of cocaine use, but no studies have documented a direct link. OBJECTIVE To determine whether low-dose cocaine administration induces cerebral vasoconstriction in healthy cocaine users. DESIGN Randomized controlled trial. SUBJECTS Twenty-four healthy and neurologically normal men (...

Background. Experimental studies have demonstrated that intracoronary platelet aggregation and thrombus formation may induce marked vasoconstriction of epicardial arteries with endothelial injury. Methods and Results. To examine the effects of intracoronary thrombus formation on coronary vasomotor tone of human epicardial arteries in vivo, we studied 15 patients who developed intracoronary thro...

BACKGROUND Noradrenergic vascular hyper-responsiveness is a hallmark of essential hypertension. To evaluate whether nitric oxide plays a role in the enhanced vascular response to norepinephrine in hypertension, we examined 32 hypertensives and 28 normotensives who were distributed in 3 experimental series. METHODS AND RESULTS In the first series, we measured the forearm blood flow (FBF) respo...

Yamaguchi O, Kaneshiro T, Saitoh S, Ishibashi T, Maruyama Y, Takeishi Y. Regulation of coronary vascular tone via redox modulation in the 1-adrenergic-angiotensin-endothelin axis of the myocardium. Am J Physiol Heart Circ Physiol 296: H226–H232, 2009. First published November 21, 2008; doi:10.1152/ajpheart.00480.2008.—We hypothesized that 1-adrenoceptor stimulation of cardiac myocytes results i...

In this manuscript, we will describe and highlight the most important potential underlying mechanisms of action inhaled sodium ibuprofenate in hypertonic saline formulation-NaIHS aerosolisable, as a probable adjuvant treatment for moderate severe pneumonia coronavirus disease 2019 (COVID-19)-associated acute respiratory distress syndrome COVID-19. both pathological entities, refer exclusively t...

Humans encounter hypoxia throughout their lives. This occurs by destiny in utero, through disease, and by desire, in our quest for altitude. Hypoxic pulmonary vasoconstriction (HPV) is a widely conserved, homeostatic, vasomotor response of resistance pulmonary arteries to alveolar hypoxia. HPV mediates ventilation-perfusion matching and, by reducing shunt fraction, optimizes systemic Po(2). HPV...