Effect of Temperature on the Heart Rate, Electrocardiogram and Certain Myocardial Oxidations of the Rat

Abstract

Deep hypothermia in the rat was studied with respect to the sequential changes in body temperature, heart rate, and electrocardiogram. In vitro assays of myocardial metabolic activity were made at temperatures ranging from 5 to 35 C. These assays strongly suggested that the in vivo cardiac dysfunctions observed at low temperatures were attributable to shifts in temperature kinetics of enzyme systems at 20 to 21 C.