Experiments were performed in vitro specifically to elucidate the underlying mechanism(s) of the attenuated adrenergic responses of eel (Anguilla rostrata) erythrocytes. This was achieved by comparing beta-adrenoceptor numbers and affinities in addition to (i) Na+/H+ exchange activity, (ii) cell swelling and (iii) cyclic AMP formation mediated by catecholamines in eel and trout (Oncorhynchus my...

The present study was designed to verify our previous hypothesis that carteolol, a beta1/beta2-adrenoceptor-blocking agent, is a nonconventional partial agonist of cardiac beta1-adrenoceptors. To this purpose, we characterized the effects of carteolol in guinea pig myocardial preparations and measured the affinities of carteolol for high- and low-affinity sites of beta1-adrenoceptors labeled by...

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...

β3-Adrenoceptor agonists have recently been introduced for the treatment of overactive urinary bladder syndrome. Their target, the β3-adrenoceptor, was discovered much later than β1- and β2-adrenoceptors and exhibits unique properties which make extrapolation of findings from the other two subtypes difficult and the β3-adrenoceptor a less-understood subtype. This article discusses three aspects...

Heart failure (HF) is a chronic clinical syndrome characterized by the reduction in left ventricular (LV) function and it represents one of the most important causes of morbidity and mortality worldwide. Despite considerable advances in pharmacological treatment, HF represents a severe clinical and social burden. Sympathetic outflow, characterized by increased circulating catecholamines (CA) bi...

  It has been shown that acute inflammation reduces the effectiveness of sympathetic nerves in the regulation of knee joint blood flow. To investigate the role of vascular β- adrenoceptors in this event, 12 NZW rabbits were maintained anaesthetized by 1 % halothane in N2O/O2, and acute knee joint inflammation was induced by intra-articular injection of 1 ml of 2% carageenan solution 24 hours be...