Role of Potassium in Regulation of Coronary Blood Flow.

Abstract

Intracoronary infusion of KC1 sufficient to elevate coronary arterial plasma K concentration to levels of from 4.23 to 12.10 milli-equivalents/liter produced increases in coronary blood flow averaging 17.7%. The changes in coronary blood flow produced by KC1 influsion did not parallel the changes in plasma K concentration. Infusion of 2,4-dinitrophenol or epinephrine, asphyxia, or increased aortic pressure (all factors which are known to increase myocardial O2 consumption and coronary blood flow) did not result in the release of K from the myocardium. Therefore, it appears unlikely that K release from active myocardium is respondible for adjustment in coronary resistance which accompanies changes in metabolic activity of the myocardium.