Thermosensitivity changes in cold-adapted rats

Cold-adapted rats (unlike non-adapted animals) respond to an acute exposure to external cold by an overshoot increase in metabolic rate and a paradoxical increase in body core temperature. In contrast to external cooling, internal cooling with the aid of a chronically implanted intravenous heat exchanger elicited comparable increase in metabolic rate, coupled with a large fall in core temperature. It is concluded that cold adaptation alters peripheral thermosensitivity (enhances cold sensitivity), while the thermosensitivity of the core is not affected by the adaptation process.