THE EFFECT OF A VITAMIN-E-DEFICIENT DIET ON AMINO-ACID LEVELS IN THE SUBSTANTIA-NIGRA, STRIATUM AND HIPPOCAMPUS OF RATS

The effects of a vitamin E deficiency diet for 15 days on amino acid c oncentrations have been studied in the substantia nigra, striatum and hippocampus of the rat. The substantia nigra showed an increase in glu tamate and GABA and a decrease of tryptophan concentration compared wi th controls. In the striatum, aspartate and glycine decreased, no chan ges were found in the amino acid concentrations in the hippocampus. Th e substantia nigra and striatum showed opposite results - an increase and decrease of amino acids respectively. The increase of glutamate fo und in substantia nigra is particularly interesting as it may suggest possible links to degenerative processes. These results suggest that v itamin E could play a crucial role in substantia nigra degeneration an d that the substantia nigra could be more sensitive to an oxidative st ress than other brain structures.