[Sympathetic mechanism of regulating heart function in acute transitory coronary insufficiency of different duration]

Experiments on 102 outbred white male rats with experimental acute transitory coronary insufficiency (ATCI) were carried out to show a consistent phasic time course of the functioning of the sympathetic cardiac activity regulation mechanism. The sympathetic neuroeffector influence on the myocardium with ATCI depends to a large measure on the intensity of the neurotransmitter biosynthesis and function of cardiomyocyte adrenoreceptors. It is suggested that the time couse of heart contractility and rhythm under ATCI is related to changes in the pre- and post-synaptic component of the sympathetic regulation mechanism of cardiac function. It is also assumed that cardiomyocyte receptors might exert a substantial influence on the possibility and development of arrhythmias. The advantages of pharmacological correction (as compared with the blockade) of sympathetic neuroeffector influences on the myocardium under ATCI are emphasized.