Inhibition by N-acetyl-aspartate of aspartate binding to a proteolipid fraction from rat cerebral cortex.

Many roles have been suggested for N-acetyl-aspartate in brain function because of it being located almost exclusively in that organ. However, its true role remains to be demonstrated. We show here that N-acetyl-aspartate: 1) binds to a hydrophobic protein fraction from the cerebral cortex of the rat, which specifically binds L-aspartate, L-glutamate, and gamma-amino-butyric acid; and 2) has a marked inhibitory effect on the aspartate binding sites of this proteolipid fraction. Structural analogs of N-acetyl-aspartate, i.e. N-carbamyl-aspartate and N-methyl-aspartate also inhibit the L-aspartate binding by the brain protein fraction used.