[Histochemical study of the adrenergic innervation of the heart in experimental myocardial infarct treated by intravenous nitroglycerin administration].

Histochemical study of the adrenergic innervation of the heart of rabbits in experimental myocardial infarction showed that the content and distribution of the mediator noradrenaline in the nerve terminals under-goes essential changes. The amount of mediator in the nerve fibers decreases not only in the zone of the infarct but also in the heart areas not involved in the infarction, particularly in the left ventricle. Changes in the fluorescence of the nerve terminals associated with redistribution of the mediator in them are described. The disorders revealed in the sympathetic nerve apparatus of the heart provide evidence that in myocardial infarction the heart reacts as a single whole; these changes may aggravate the course of the infarction. Intravenous nitroglycerin administration helps to preserve the mediator in the nerve terminals, which is regarded as a favourable effect of the drug.