Hibernation reduces pancreatic amylase levels in ground squirrels

Comp Biochem Physiol A Mol Integr Physiol. 2003 Mar;134(3):573-8. doi: 10.1016/s1095-6433(02)00363-x.

Abstract

Pancreatic enzyme levels in mammals are influenced by food intake and dietary composition. In this study, we examined the activity and expression of pancreatic amylase in a hibernating mammal, a natural model for long-term fasting. Pancreatic tissues were obtained from summer-active 13-lined ground squirrels and hibernating squirrels that had not eaten for at least 6 weeks. Amylase specific activity was reduced by approximately 50% in the torpid hibernators compared with summer squirrels, and immunoblot analysis revealed that amylase protein expression was reduced by approximately 40% in the hibernators. Similar reductions in amylase specific activity were observed in interbout euthermic hibernators. These results support a strong influence of food intake on pancreatic enzyme expression in hibernating mammals. The maintenance of basal levels of this key digestive enzyme at approximately 50% of summer values despite the extended winter fast likely facilitates the rapid resumption of digestive function after terminal arousal in the spring.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Amylases / metabolism*
  • Animals
  • Blotting, Western
  • Body Weight
  • Female
  • Gene Expression Regulation, Enzymologic*
  • Hibernation / physiology*
  • Male
  • Pancreas / enzymology*
  • Sciuridae / physiology*
  • Seasons
  • Wisconsin

Substances

  • Amylases