OBJECTIVES The study investigated whether beta-adrenoceptor antagonists augment the hypertrophic response of cardiomyocytes evoked by norepinephrine. BACKGROUND In adult ventricular cardiomyocytes, stimulation of alpha- but not beta-adrenoceptors induces myocardial hypertrophy. Natural catecholamines, like norepinephrine, stimulate simultaneously alpha- and beta-adrenoceptors. We investigated...

Gorman, Mark W., Martin Farias III, Keith N. Richmond, Johnathan D. Tune, and Eric O. Feigl. Role of endothelin in -adrenoceptor coronary vasoconstriction. Am J Physiol Heart Circ Physiol 288: H1937–H1942, 2005. First published December 9, 2004; doi:10.1152/ajpheart.01076.2004.—It has been proposed that -adrenoceptor vasoconstriction in coronary resistance vessels results not from -adrenoceptor...

At the β1-adrenoceptor, CGP 12177 potently antagonizes agonist responses at the primary high-affinity catecholamine conformation while also exerting agonist effects of its own through a secondary low-affinity conformation. A recent mutagenesis study identified transmembrane region (TM)4 of the β1-adrenoceptor as key for this low-affinity conformation. Others suggested that TM4 has a role in β1-...

Recent evidence suggests that the quinazoline-based 1-adrenoceptor antagonists, doxazosin and terazosin, exhibit a potent apoptotic effect against prostate tumor epithelial cells, whereas tamsulosin, a sulfonamide-based 1-adrenoceptor antagonist, was ineffective in inducing a similar apoptotic effect against prostate cells (Cancer Res., 60: 4550–4555, 2000). In this study, to identify the preci...

we investigated the a,-adrenoceptor subtypes of rabbit saphenous vein which has a mixed functional population of α1 and α2 -adrenoceptors. lateral saphenous veins were obtained from male rabbits weighing 3.20-4 kg, which were killed by overdose with pentobarbitone sodium (i.v. injection). they were easily dissected out and placed in cold, oxygenated modified krebs-henselite solution (krebs). ea...

The purpose of our study was to investigate the inotropic response to the endogenous agonist norepinephrine mediated through alpha-1 adrenoceptors and to compare this response to that mediated through beta-adrenoceptors in failing human ventricular myocardium. We studied ex vivo the inotropic effect of norepinephrine in isometrically contracting trabecular myocardium from both ventricles of exp...

Alterations in platelet o2-adrenoceptor and mononuclear leucocyte ß2-adreno-ceptor characteristics in primary hypertension have been studied quite exten-sively The results of these studies are not consistent, which may be due to therelatively small number of subjects in most of the studies. In the present study,the o2-adrenoceptor characteristics were compared between 65 hyperte...

BACKGROUND Naftopidil, an α1-adrenoceptor blocker, has been clinically used for the treatment of benign prostate hyperplasia and hypertension. Emerging evidence has shown that naftopidil exhibits an antitumor effect on a variety of cancer types including prostate cancer. The aim of the present study was to investigate naftopidil-induced apoptosis in human malignant mesothelioma cells and to she...

Catecholamines, either endogenous hormones or a variety of exogenous synthetic pharmacological agents, bind to adrenoceptors to mediate their ultimate clinical effects [21]. Since adrenoceptors mediate many cardiovascular responses, pharmacological stimulation and inhibition of adrenoceptors may be useful to the anaesthetist. Ahlquist described originally two adrenoceptor subtypes (alpha and be...

1 Cetamolol is a new 3-adrenoceptor blocking agent shown in animals to have moderate PI -adrenoceptor selectivity and partial agonist activity. 2 In healthy normal volunteers, PI -adrenoceptor blockade was measured as the reduction of exercise-induced tachycardia, systolic blood pressure, and double product at 2, 8, and 24 h after a single oral dose of 10, 25, and 50 mg cetamolol. 3 P1-adrenoce...