Purpose: The aim of this study was to evaluate histologically and immunohistochemically the cytoprotective effects thymoquinone (THQ) against isoproterenol (ISO)-induced aortic tissue damage.
 Materials Methods: Rats were divided into four groups (n=8). Control group (Control); untreated rats, Thymoquinone (THQ); 20 mg / kg intragastrically (ig) THQ at 24 hour intervals for 8 days, Isoprot...

The influence of elastic recoil and restoring forces on diastolic left ventricular pressure decay and minimum left ventricular pressures has been demonstrated in animal models but has not been studied in the human heart. To investigate this issue in the normal human left ventricle, we studied eight patients with chest pain and normal coronary arteries with simultaneous measurement of left ventr...

Isoproterenol plus guanylyl imidodiphosphate (Gpp(NH)p) activate frog erythrocyte adenylate cyclase to a level much higher than the sum of the activities produced by the catecholamine and the synthetic nucleotide tested separately. Propranolol, the beta-receptor blocking agent, failed to inhibit activity when added after the enzyme system had been preincubated with both isoproterenol and Gpp(N...

The enzymatic activity of the mitochondrial oligomycin-sensitive ATPase was investigated during isoproterenol-induced cell injury of myocardium, using rat heart homogenates and a potentiometric method. The enzymatic activity of the oligomycin-sensitive ATPase and the inhibitory action of oligomycin do not show significant alterations upon treatment with isoproterenol. These results are inconsis...

In canine atrial muscles, carbachol and nicorandil hyperpolarized the resting membrane potential and shortened the action potential duration. In the presence of carbachol or nicorandil, isoproterenol further hyperpolarized the resting membrane potential and shortened the action potential duration. Isoproterenol significantly increased the plateau duration in the presence of nicorandil, but furt...

beta-Adrenergic agonists influence electrolyte reabsorption in the proximal tubule, loop of Henle, and distal tubule. Although isoproterenol enhances magnesium absorption in the thick ascending limb, it is unclear what effect, if any, beta-adrenergic agonists have on tubular magnesium handling. The effects of isoproterenol were studied in immortalized mouse distal convoluted tubule (MDCT) cells...

PURPOSE To determine whether the adrenergic agonists epinephrine and isoproterenol regulate fluid flow across endothelial cells cultured from the human aqueous outflow pathway and to evaluate associated cellular mechanisms. METHODS Confluent monolayers of human trabecular meshwork (TM) or Schlemm's canal endothelial (SCE) cells were grown on porous filter supports. The monolayers were perfuse...

Saini, Harjot K., Onkar N. Tripathi, Shetuan Zhang, Vijayan Elimban, and Naranjan S. Dhalla. Involvement of Na /Ca exchanger in catecholamine-induced increase in intracellular calcium in cardiomyocytes. Am J Physiol Heart Circ Physiol 290: H373–H380, 2006. First published September 9, 2005; doi:10.1152/ajpheart.00613.2005.—Although sarcolemmal (SL) Na /Ca exchanger is known to regulate the intr...

Recently, we showed that compared with the A/J inbred mouse strain, C57BL/6J (B6) mice have an athlete's cardiac phenotype. We postulated that strain differences would result in greater left ventricular (LV) hypertrophy in response to isoproterenol in B6 than A/J mice and tested the hypothesis that a differential response could be explained partly by differences in beta-adrenergic receptor (bet...

Six patients with transient or permanent visual loss associated with migraine are presented. In 3 patients with monocular and one patient with binocular episodes of transient visual loss subsequent visual episodes were relieved by prompt inhalation of isoproterenol. The authors review the possible mechanisms of action of isoproterenol in migraine and present evidence to support the prophylactic...