Cold resistance of the brain during hibernation: I. K + transport in cerebral cortex slices

The brains of the hibernating hamsters and 13-lined ground squirrels maintain Na + and K + at the same concentrations as in the awake state. The ability of slices of the cerebral cortex when incubated in vitro to accumulate or retain K + is similar in the awake hamster and rat at both 38 and 5 ° C. On the other hand, slices of cerebral cortex from the hibernating hamster retained slightly more K + at 5 °C than did those of awake hamster or rat. It was concluded that the cerebral cortex of the awake hamster is probably not cold resistant with respect to the maintenance of cation balance. Further, the cold resistance that exists in the cerebral cortex of the hibernating hamster is largely destroyed when the brain is disrupted by slicing.