Effects of Vagus Stimulation and of Acetylcholine on Myocardial Contractility, O2 Consumption and Coronary Flow in Dogs

During vagus nerve stimulation the heart rate was maintained at a constant level by an electric pacemaker. Under these conditions no changes were found in ventricular function curves, myocardial oxygen consumption and coronary blood flow. Acetylcholine infusion, with heart rate maintained constant, caused decreased myocardial contractility and coronary and peripheral vasodilation.