Metyrapone-induced thermogenesis in cold- and heat-acclimated rats

Metyrapone caused significant increase of VO2 in cold-acclimated rats, but not in warm controls and heat-acclimated rats. Plasma FFA decreased, while plasma glycerol increased in all groups. Glycerol increase was less in heat-acclimated rats than in other groups. FFA/glycerol molar ratio decreased most in cold-acclimated rats.