Affiliation:
1. Department of Cardiorespiratory Diseases, Walter Reed Army Institute of Research, Washington, D. C.
Abstract
The effect was determined of changes in heart rate and of intracoronary isoproterenol, levarterenol, and epinephrine on coronary flow in the stopped and beating heart. It was possible by this means to estimate the relative action of these variables on the extravascular and intravascular resistance of the coronary bed in a heart perfused at constant pressure. As heart rate was increased extravascular resistance rose, but intravascular resistance fell to a greater extent indicating a fall in net coronary resistance. Isoproterenol had the greatest and epinephrine the least effect in decreasing the total coronary resistance. The three drugs tested caused only a small fall in extravascular resistance. Since the effect was small, it was concluded that extravascular resistance can be ignored in determining the direct effect of these drugs upon the coronary vasculature.
Publisher
Ovid Technologies (Wolters Kluwer Health)
Subject
Cardiology and Cardiovascular Medicine,Physiology
Cited by
55 articles.
订阅此论文施引文献
订阅此论文施引文献，注册后可以免费订阅5篇论文的施引文献，订阅后可以查看论文全部施引文献