Seasonal changes in cryoprotectants concentrations in Helix pomatia snails

Terrestrial snails are often exposed to freezing. Therefore, we investigated seasonal shifts in hemolymph concentrations of cryoprotectants such as glycerol and glucose. We also investigated whether summer acclimation to cold and short-day photoperiod induced synthesis of cryoprotectants in Helix pomatia snails. Concentrations of the both cryoprotectants were elevated in winter and reduced in summer. These changes, however, were not correlated with shifts in liver glycogen content. Summer acclimation to cold (5 degrees C) and short-day photoperiod evoked a selective increase in glycerol concentration. In conclusion, glycerol may play a role in adaptation of the snails to winter cold and glucose is rather unlikely to provide the cryoprotection.