L-argininosuccinate modulates L-glutamate response in acutely isolated cerebellar neurons of immature rat.

Fura-2 microfluorometry revealed that as little as 10(-13) M L-argininosuccinate, an intermediate of the L-arginine synthesizing pathway, is sufficient to reduce the increase in intracellular free calcium produced by L-glutamate in the acutely isolated cerebellar neurons of immature rats. In these neurons L-argininosuccinate also reduced the response to quisqualate, but not the response to kainate or N-methyl-D-aspartate. The results suggest that L-argininosuccinate may function as a transmitter or modulator in the brain.