| road proximity increases risk of skeletal abnormalities in wood frogs from national wildlife refuges in alaska. | skeletal and eye abnormalities in amphibians are not well understood, and they appear to be increasing while global populations decline. here, we present the first study of amphibian abnormalities in alaska. | 2008 | 18709167 |
| cryoprotectant production in freeze-tolerant wood frogs is augmented by multiple freeze-thaw cycles. | ice nucleation across the skin of wood frogs (lithobates sylvaticus) rapidly induces endogenous production of glucose, a cryoprotectant necessary for freeze tolerance. in laboratory studies of freeze tolerance, wood frogs are cooled slowly, often at -0.05°c h(-1), to facilitate high cryoprotectant production and survival. under natural conditions in alaska, however, wood frogs accumulate maximal tissue glucose concentrations while cooling at much faster rates, -0.35° to -1.6°c h(-1), and in addi ... | 2017 | 27327184 |
| membrane adaptation in phospholipids and cholesterol in the widely distributed, freeze-tolerant wood frog, rana sylvatica. | maintaining proper membrane phase and fluidity is important for preserving membrane structure and function, and by altering membrane lipid composition many organisms can adapt to changing environmental conditions. we compared the phospholipid and cholesterol composition of liver and brain plasma membranes in the freeze-tolerant wood frog, rana sylvatica, from southern ohio and interior alaska during summer, fall, and winter. we also compared membranes from winter-acclimatized frogs from ohio tha ... | 2014 | 24504263 |
| enzymatic regulation of glycogenolysis in a subarctic population of the wood frog: implications for extreme freeze tolerance. | the wood frog, rana sylvatica, from interior alaska survives freezing at -16°c, a temperature 10-13°c below that tolerated by its southern conspecifics. we investigated the hepatic freezing response in this northern phenotype to determine if its profound freeze tolerance is associated with an enhanced glucosic cryoprotectant system. alaskan frogs had a larger liver glycogen reserve that was mobilized faster during early freezing as compared to conspecifics from a cool-temperate region (southern ... | 2013 | 24236105 |
| hibernation physiology, freezing adaptation and extreme freeze tolerance in a northern population of the wood frog. | we investigated hibernation physiology and freeze tolerance in a population of the wood frog, rana sylvatica, indigenous to interior alaska, usa, near the northernmost limit of the species' range. winter acclimatization responses included a 233% increase in the hepatic glycogen depot that was subsidized by fat body and skeletal muscle catabolism, and a rise in plasma osmolality that reflected accrual of urea (to 106±10 μmol ml(-1)) and an unidentified solute (to ~73 μmol ml(-1)). in contrast, fr ... | 2013 | 23966588 |