REGIONAL CHANGES IN AMINO-ACID LEVELS OF THE NEONATE RAT-BRAIN DURINGANOXIA AND RECOVERY

The aim of this study was to compare the changes in amino acids (alani ne, aspartate, GABA, glutamate, glutamine, glycine, serine taurine) th at are produced in different regions of the neonate brain (telencephal on, diencephalon cerebellum, brain stem) following a survivable period of anoxia and after the re-establishment of air respiration. Anoxia p rovoked different responses in the different regions. The changes duri ng the anoxic period were as follows. In the brain stem there was a de crease in aspartate, in the telencephalon there was a significant incr ease in GABA and alanine and a decrease in aspartate, in the diencepha lon, glutamate and GABA increased, and in the cerebellum, glycine and alanine levels were enhanced. The changes during recovery were even mo re dissimilar. Here the greatest shifts were seen in the brain stem wi th increases in glutamine, GABA, aspartate, glycine, serine, alanine, and taurine. In the telencephalon glutamate fell and alanine increased , in the diencephalon GABA increased, and in the cerebellum, glutamate fell while glycine and alanine increased. In none of the major brain regions did the pattern of changes in neurotransmitters correspond to that seen in anoxic tolerant species.