[Free amino acid concentration in the brain during hypothermia and at different times following the hypothermic period].

Content of 19 amino acids was estimated in rat brain hemispheres, cerebellum, midbrain and medulla oblongata both under conditions of hypothermia (20 degrees) and within 1, 3, 7, 15, 45 and 60 days after selfwarming. Hypothermia, depending on its length (5-10, 60 and 120 min), caused various alterations in the pool of amino acids, dissimilar in the brain regions studied. The phasic alterations in the amino acid content were observed in brain tissues during the posthypothermic period. Normalization of the amino acid pool occurred within the 60 day. Hypothermia and posthypothermic state were accompanied by similar alterations in the amino acid content either in brain hemispheres and cerebellum or in midbrain and medulla oblongata.