Toxic cardiac effects of catecholamines: role of β-adrenoceptor downregulation

Publication date 12th December 2002
Authors Fazia Brouri, Laurent Findji, Odile Médiani, Nathalie Mougenot, Naima Hanoun, Gilles Le Naour, Michel Hamon, Philippe Lechat

Summary

The aim of our study was to analyse the mechanisms underlying cardiac toxicity caused by β-adrenoceptor stimulation and the relationships with their associated downregulation during heart failure. We used the experimental model of coronary artery ligation-induced myocardial infarction in male Wistar rats. In order to increase β-adrenergic stimulation, rats were subjected to a 15-day chronic isoprenaline administration (30 μg/kg/h). Isoprenaline administration induced haemodynamic inotropic compensation, almost abolished in vitro inotropic response to isoprenaline on papillary muscle (P