INFLUENCE OF VARIATION IN ENVIRONMENTAL TEMPERATURE ON THE ACUTE TOXICITY OF RESERPINE AND CHLORPROMAZINE IN MICE

Abstract
The acute toxicity of chlorpromazine in mice is 18 times higher in an environment of 4 °C than in a thermoneutral environment of 30 °C. Under similar conditions the acute toxicity of reserpine increases about 1200 times. These findings confirm the earlier suggestion that these drugs cause hypothermia by different mechanisms of action. Increased acute toxicity of these drugs was also noticed at a higher temperature (36 °C).At 4 °C, after chlorpromazine, death occurred earlier than after reserpine. Reserpine produced a transient increase in oxygen consumption (in rats) which helped maintain body temperature but resulted in a more rapid loss of heat from the body. This would explain the difference in time of death and might explain the difference in ultimate mortality between the animals treated with these two drugs.