Effect of chronic temperature stress on liver metabolism in Spermophilus lateralis, Spermophilus tereticaudus, and Amnospermophilus leucurus

Abstract

1. Liver oxidative enzyme activities, protein content, and mass were measured in control, cold- and heat-acclimated Spermophilus lateralis, Spermophilus tereticaudus, and Amnospermophilus leucurus. 2. S. tereticaudus and A. leucurus, but not S. lateralis, responded to chronic temperature stress with significant changes in liver mass. 3. Adaptive changes in oxidative enzyme levels/activities occurred in all three species, perhaps contributing to greater nonshivering thermogenesis in the cold and chemical thermosuppression in the heat. 4. In contrast to responses of brown adipose tissue, liver enzymatic responses suggest an intrinsic physiological difference between the desert and mountain species.