Oxygen Consumption Correlated with the Thermal Reactions of Young Rats to Ergotoxine.

摘要

Hypothermic responses to ergotoxine of young rats (in the pre-regulatory age range) were associated with decreased oxygen consumptions in one strain studied (Wistar), but a second strain (Sprague-Dawley) displayed a lack of correlation with some animals showing slight increases in metabolism. Since the correlation in the Wistar strain represents a metabolic reaction that could have occurred through the operation of van't Hoff's Law, interference with metabolism is questionable. The hypothermias may be due to unselective stimulation of heat-production and heat-loss centers, with the latter predominating during this age range. Hyperthermic responses in regulating rats were closely correlated with increased oxygen consumption. Since the increase in metabolic rate was approximately 2.5 times that which might be anticipated from the independent operation of van't Hoff's Law, a direct stimulation of metabolism must be responsible for it. Available evidence indicates that this metabolic stimulation is mediated through the action of ergotoxine on the hypothalamic thermoregulatory centers.