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Published on: August 16, 2016
Effect of α2-adrenoceptor stimulation on cardiac activity in rats
T L Zefirov1, N I Ziyatdinova, L I Khisamieva
1Department of Anatomy, Physiology, and Human Health Protection, Kazan (Volga Region) Federal University, Kazan, Russia, zefirovtl@mail.ru.
Abstract:
We studied the effect of α2-adrenoceptor stimulation with clonidine on BP and cardiac activity in rats. Variations in BP and chronotropism of the heart were studied in vivo after bolus injection of clonidine. In vitro experiments were performed to evaluate a dose-dependent change in myocardial contractility of the atria and ventricles after treatment with clonidine in concentrations of 10(-9)-10(-5) M. α2-Adrenoceptor stimulation with clonidine had a negative chronotropic and inotropic effect and induced the decrease in systolic BP of rats.
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