[Systems for regulating the level of Ca2+, cyclic nucleotides, and reverse absorption of neurotransmitters in isolated nerve endings of the rat brain during development of myocardial infarct].

The systems regulating the levels of Ca(2+)-Mg2+, Ca(2+)-ATPase and potential-dependent absorption of Ca2+ as well as content of cyclic nucleotides, beta-adrenoreceptors, activities of adenylate-, guanylate cyclases and phosphodiesterase were studied in the synaptosomes of rat brain cortex in evolving myocardial infarction. In addition, reverse absorption of noradrenaline, dopamine and serotonin was studied. In one of the animal groups myocardial infarction was simulated after stress. The myocardial infarction, affecting the systems of Ca2+ regulation, caused an increase in reverse absorption of dopamine and serotonin simultaneously with accumulation of lactate in the synaptosomes. In myocardial infarction developed after stress adenylate cyclase was activated, reverse absorption of dopamine was decreased and the content of lactate tended to decrease as compared with the infarction formed without stress effects.