Dynamic effects of acute cooling in body temperature regulation of the euthermic warm-acclimated golden hamster (Mesocricetus auratus).

During the dynamic phase of external cooling of euthermic golden hamsters in the initial period of metabolic response, peripheral body temperature is the decisive control variable determining the level of metabolic heat production. Under these conditions the rate as well as the magnitude of the peripheral body temperature change constitute the effectual input to the controller of body temperature. The apparent sensitivity with which the regulator drives the metabolic response to unit change of the peripheral temperature is in an inverse relation to the rate of peripheral temperature change. This parameter, despite its limited significance can serve as a working index characterising the thermoregulatory system in different groups of experimental animals of the same species providing that the actual conditions of the experiment are comporting.