Effect of α2-Adrenergic Receptor Stimulation on the Isolated Rat Heart against the Background of I<inf>f</inf> Blockade

Abstract

© 2020, Springer Science+Business Media, LLC, part of Springer Nature. The study examined the effect of α2-adrenoreceptor (α2-AR) activation against the background of preliminary blockage of If on the performance of Langerndorff-isolated rat heart. Stimulation of α2-AR in isolated rat hearts against the background of ZD7288 in concentrations of 10—9 M and 3×10—5 M changed the negative dynamics of myocardial inotropy to positive (by 25 and 38%; p'0.05). Activation of α2-AR produced opposite effects on HR. If blockade abolished tachycardia caused by activation of α2-AR; HR deceleration in response to α2-AR agonist against the background of If blocker in a concentration 10—9 M was 41% (p'0.05). We observed negative dynamics of coronary flow (by 38%; p'0.05) in isolated adult rat hearts after application of α2-AR agonist against the background of If blockade (10—9 M).