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Published on: September 17, 2015
Histidine increases beta-adrenoreactivity of myocardium in frogs
A N Trukhin1, V I Tsirkin, E N Sizova
1Department of Anatomy, Physiology, and Valeology, Vyatka State Humanitarian University.
Abstract:
Histidine (3x10(-5) g/ml) had no effect on contractility and chronoinotropic relationships in frog myocardium, but rapidly and reversibly increased myocardial beta-adrenoreactivity (increased myocardial response to 7x10(-8), 3x10(-7), and 4x10(-6) g/ml epinephrine) and potentiated the positive effect of epinephrine (7x10(-8), 3x10(-7) g/ml) on chronoinotropic relationships in the myocardium. Histidine is considered to be a component of endogenous sensitizer of beta-adrenoceptors in human blood modulating the function of cardiomyocytes.
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