[Homocarnosine levels in repeated hypothermia and hibernation]

Compulsory cooling of rats (20 degrees) and susliks (20 degrees-10 degrees) leads to a considerable decrease of homocarnosine in cerebral hemispheres in midbrain and diencephalon and cerebellum. When hypothermia is repeated 4 or 7 times (in every 24 h) a more considerable decrease in the homocarnosine quantity in the rat brain takes place and it is not normalized after self-warming of the organism. After 11-12-fold hypothermia, when a certain adaptation of animals to cooling is developed, the second increase of homocarnosine content with subsequent normalization of its level in great cerebral hemispheres and in cerebellum at self-warming is observed. In dynamics of the hibernation (1, 7 and 30 days) either preservation of normothermal level or a certain increase of the homocarnosine content in all areas of the suslik brain under examination is observed.