Adrenergic Drugs and Blockade on Coronary Arterioles and Myocardial Contraction

Abstract
The 3 adrenergic substances, epinephrine, levarterenol and isopropylarterenol, were injected into a coronary artery of anesthetized dogs while recording the coronary artery flow (electromagnetic meter) and pressure. The effects of these substances on the peripheral coronary pressure (PCP) were recorded by occluding the flow proximal to the pressure gage. All 3 substances caused a qualitatively similar increase in myocardial contraction and dilation of the coronary arterioles.