Sexual difference in thermoregulatory ability of rats exposed to cold and heat

摘要: Abstract 1. 1.Marked sexual differences in the thermoregulatory responses to acute exposure cold (5°C, 90 min) and heat (35°C, 60 were found rats. 2. 2.A significantly smaller increase cold-induced shivering as well oxygen consumption was observed females than males despite same extent of fall colonic temperatures both sexes. 3. 3.Non-shivering thermogenesis tested by norepinephrine less warm- cold-acclimed rats, but not different sexes heat-acclimated ones. 4. 4.Ovariectomy potentiated cold- norepinephrine-induced production shivering. On other hand, orchidectomy did influence these responses. These results suggest that female gonadal hormones are responsible for manifestation difference heat. 5. 5.The skin temperature after greater time lowest level more rapid males, although skinfold thickness 6. 6.Therefore, insulation through peripheral vascular adjustments seems be involved occurrence cold. Moreover, also observed. 7. 7.The present indicate respond thermal stresses efficiently, namely with higher body possibly at least.