|MadSci Network: Biochemistry|
I guess that I should state that I am not a real expert in cryobiology. There are two deleterious consequences of the accumulation of ice crystals in cells: the ice may cause mechanical stress and it can lead to osmotic stress, either at the time of ice formation or upon thawing. Depletion of intracellular water should reduce the potential damage. This can be accomplished by having the solution outside the cell contain a lower concentration of water than is present inside the cell. The glycerol can enter the cell. I believe that this prevents a loss of cell volume, which would otherwise occur with the exit of a lot of water. By maintaining the cell volume, the salt concentration is also maintained. But I could be wrong about this part. The effects of the glycerol, or other cryoprotectants, are not understood completely.
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