EFFECT OF OUABAIN ON THE CORONARY CIRCULATION AND OTHER CIRCULATORY FUNCTIONS IN INTACT ANESTHETIZED DOGS

¹ Departments of Pharmacology and Pathology, School of Medicine, University of Pennsylvania and the Edward B. Robinette Foundation, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania

The effects of small and large "therapeutic" doses of ouabain have been studied in the lightly anesthetized intact dog by methods which have been largely developed and refined in this laboratory. By this means a more complete set of data has been obtained than has been previously possible in the intact animal.

The most striking change produced by ouabain was an increase in coronary resistance. As a result of this, there was a decrease in coronary flow. Cardiac oxygen consumption was maintained at the expense of an increased coronary arteriovenous oxygen difference. There was also an increase in the mean arterial blood pressure and a decrease in both pulse rate and cardiac output. Mechanical efficiency was maintained better than would have been expected without ouabain in view of the rise in arterial blood pressure.