[Mechanism of action of vasodilator agents on the collateral blood flow into an area of acute myocardial ischemia].

In acute experiments staged on dogs subject to investigation was collateral coronary circulation studied by registering the retrograde blood flow and the pressure in the ligated coronary artery. It is shown that atropinization (0.05 mg/kg) does not change the positive action of papaverine and diethyphen (2 mg/kg) on the inflow of blood into the area of myocardial ischemia and enhances the beneficial effect on euphylline (4 mg/kg). Preliminary introduction of octadine (5 mg/kg) had no material influence on the nature of the diethyphen action, but greatly weakened that of euphylline and reduced the effect of papaverine. The vasodilating agents attenuated for a short while a pituitrin-induced (0.5 U/kg) spasm of the collaterals and vessels in the ischemic area of the myocardium.