Lack of a significant protective effect of augmented circulating glucose on the ischemic myocardium.BJ.

Infusion of glucose alone or glucose with insulin in cats subjected to acute myocardial ischemia did not alter the hemodynamic response of the cats to coronary artery ligation. Furthermore, determination of myocardial creatine phosphokinase (CPK) (ATP:creatine N-phosphotransferase, EC 2.7.3.2) activities failed to reveal a protective effect of glucose and insulin upon the status of the developing infarct in the ischemic myocardium. However, glucose and insulin apparently promote clearance of CPK from the plasma and inhibit proteolysis during the early phase of myocardial ischemia. These actions may be of value in generalized adaptive response of the animal to the stress of ischemia, but does not per se appear to diminish the spread of the ischemic damage within the heart not to limit the extension of the evolving infarct.