Abstract
Endogenous opioid peptides have been shown to increase in heat stroke attacks and it has been suggested that they are involved in thermoregulation. The aim of the present investigation is to study the effect of naloxone pretreatment on the development of heat stroke in a sheep model. We observe that naloxone decreases the extent of heat stroke signs and some of the induced changes in enzymes and hormones. These observations indicate that naloxone may be a valuable drug in the prevention of heat stroke attacks in susceptible individuals.