[Mechanism of the antianginal action of oxyfedrine]

Oxyphedrine was found to depress the tonicity of coronary vessels, increase the coronary circulation volume, the oxygen uptake by the heart and also to exert a positive inoand chronotropic action in test with urethan and cloralose anesthetized cats. These effects were caused by stimulation of the beta-adrenoreceptors of the heart and vessels. In non-anesthetized cats oxyphedrine did not produce tachycardia. Furthermore, under certain conditions (when superimposed on a preliminary administration of practolol- a beta-blocking agent) oxyphedrine can exert a direct inhibitory action on the myocardium.