Seasonal effects of dehydration on glucose mobilization in freeze-tolerant chorus frogs (Pseudacris triseriata) and freeze-intolerant toads (Bufo woodhousii and B. cognatus).

It has been hypothesized that freeze-tolerance in anurans evolved from a predisposition for dehydration tolerance. To test this hypothesis, we dehydrated summer/fall-collected and winter acclimated freeze-tolerant chorus frogs and dehydration-tolerant, but freeze-intolerant, Woodhouse's and Great Plains toads to 25% and 50% body water loss (BWL). Following treatments, we measured glucose, glycogen, and glycogen phosphorylase and glycogen synthetase (summer/fall only) activities in liver and leg muscle.