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Adrenal reactivity of the circulation and of several metabolic and regulatory systems, which had been induced by narcosis and surgical trauma, was studied on 50 mongrel dogs. Operative trauma (thoracotomy) done under thiopental sodium narcosis was accompanied with the moderately elevated adrenal reactivity of the circulation and essentially unchanged metabolic processes. Changes in the cardiac contractility and pump function induced by catecholamines are mediated through cardiac and vascular beta-adrenergic mechanism. These metabolic changes are determined by the state of adrenergic mechanisms. At the same time there is no distinct correlation between these changes and beta-adrenoreceptor state.

In dogs with experimental mitral valve incompetence, by the end of the adaptation stage (2nd week) the cardiac functional reserve decreases; the decrement is correlated with the exhaustion of the reserve of catecholamine synthesis evident from the decrement of their precursors in the myocardium and adrenals as well as from the destruction of plentiful cells of the adrenal medulla, accompanied by development of necrosis, dystrophy, and disturbances of vascular permeability in the adrenal glands. In the initial period of the compensatory stage (1st month) a considerable activation of the catecholamine synthesis takes place, together with their increase in the right ventricular myocardium and in the adrenals.