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Published on: June 11, 2020
Selective Blockade of α2-Adrenoceptor Subtypes Modulates Contractility of Rat Myocardium
T L Zefirov1, L I Khisamieva2, N I Ziyatdinova2
1Department of Anatomy, Physiology, and Human Health Protection, Kazan (Volga Region) Federal University, Kazan, the Republic of Tatarstan, Russia. zefirovtl@mail.ru.
Abstract:
The study examined the dose-dependent effects of selective antagonists of α2A/D-, α2B-, and α2C- adrenoceptors applied in concentrations of 10-9-10-5 M on atrial and ventricular contractility of rat myocardium in vitro. Selective blockade of each α2-adrenoceptor subtype affected the contractile force of the atrial and ventricular strips. Various concentrations of α2A/D- and α2C-adrenoceptor antagonists produced positive inotropic effect on ventricular strips and negative effect on atrial strips. α2B-Adrenoceptor blocker in the majority of the tested concentrations produced a positive inotropic effect in both atria and ventricles.
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