Recent data reported from this laboratory have documented myocardial functional depression in endotoxin shock. The purpose of the present study was to determine the effects of insulin on the dysfunctioning canine myocardium subjected to lethal endotoxin shock. Experiments were conducted on isolated working left ventricular preparations in which LD90-100 endotoxin was administered prior to, or following, isolation of the heart. Determinations of myocardial performance were conducted under the conditions of controlled mean aortic pressure and cardiac output. Myocardial dysfunction occurred between 2 and 6 h postendotoxin, as evidenced by significantly increased left ventricular end-diastolic pressure, decreased power, and depressed negative dP/dt, although blood glucose concentrations were maintained at control values. Intraatrial infusions of insulin at rates of 6 U/min reversed all signs of myocardial dysfunction. During insulin infusion, heart rates decreased (p less than 0.02) and myocardial lactate uptake increased (p less than 0.02), while oxygen uptake and coronary blood flow were insignificantly altered.
The present study was conducted to explore influences modifying glucose uptake in canine blood administered LD100 E. coli endotoxin. Particular emphasis was given to assay the role of the white blood cell (WBC) in glucose utilization. Significant increases in glucose uptake and lactic acid production, attributed to increased activity of the WBC, were observed 1-3 h after endotoxin was added to blood in vitro. Although a net increase in glucose utilization was noted, endotoxin simultaneously exerted adverse effects by depressing glucose uptake below predicted values (Q10 = 2.12 with LD100 endotoxin vs. 2.78 in saline controls) and increasing WBC mortality rate. Blood from dogs pretreated with sublethal doses of endotoxin in vivo utilized glucose at an accelerated rate when subjected to endotoxin in vitro. Excess glucose was consumed because of elevated numbers of white blood cells although additional glucose requirements after endotoxin were independent of temperature between the ranges of 34-41 degrees C. All animals pretreated with daily sublethal injections of endotoxin for 3 days survived superlethal doses of endotoxin.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.