[Mechanism of decrease in noradrenaline content in the myocardium under the effect of various industrial poisons]

Alteration in content of catecholamines, DOPA and the monoaminooxidase activity (MAO) were observed in rat myocardium under prolonged administration of cobalt (5 mg of the metal per 1 kg of body weight). A correlation was observed between the decrease in noradrenaline content and the MAO activation. In myocardium content of noradrenaline was approximately constant in simultaneous administration of an MAO inhibitor nyalamide (20 mg/kg of body weight) and cobalt within 10 days. In heart muscle the adrenaline concentration did not depend on the MAO activity; content of the amine was increased when the content of noradrenaline decreased and the MAO activity increased.