[Cardiac output and systemic pressor reactions].

In acute experiments on cats, participation of coronary and systemic fractions was studied in suppression of the carotid sinus baroreceptors with occlusion of the carotid arteries and under stimulation of the tibial nerve's afferent fibers. In most of the tests, systemic fraction was reduced under occlusion of the carotid arteries and increased under stimulation of the tibial nerve. The coronary fraction was always increased. The alterations in cardiac output (the sum of systemic and coronary fractions) differ considerably from those in systemic fraction. The role of coronary fraction in evaluation of cardiac output under several reflex pressor reactions, is discussed.