Thermal and metabolic responses of repetitively immobilized rats to acute heat exposure.

Repetitively immobilized rats (3 hr/day, 4 weeks) exhibited less increase in the colonic temperature during acute heat exposure at 38 degrees C for 60 min. The magnitude of increase in oxygen consumption during heat exposure did not differ between the controls and the stressed rats. The results suggest that an immobilization stress could develop cross adaptation to heat, possibly by means of enhanced heat dissipating capacity.