Effect of experimental infarct on the mortality rate in alloxan-diabetic rats.

The authors report the wide mortality observed in alloxan diabetic rats infarcted with large doses of isoproterenol. The experimental data are in line with the results of clinical studies testifying that the diabetic disease involves the cardiovascular system and affects the prognosis of myocardial infarct. These experiences do not permit to define the direct mechanism(s) responsible for the high mortality in diabetic infarcted rats over controls (diabetic not infarcted); however these results give rise to a discussion on the following topics: 1. The damage of intramural coronary vessels as a cause of depressed cardiac contractility in diabetic rats. 2. The role of reduced plasmatic levels of insulin in depressing myocardial performance in alloxan diabetic rats. 3. The hyperglycaemia-provoking effect of isoproterenol as a contributing factor in the death of diabetic rats. 4. The possible direct action of diabetogenic doses of alloxan on the myocardium.