Lasting effect of NO on glutamate release in rat striatum revealed by continuous brain dialysis.
The effect of nitric oxide (NO) on glutamate release in the brain of freely moving rats was investigated using a new, high time-resolution microdialysis system. Coperfusion with veratridine (VER) and NO donors increased glutamate release above than that obtained with VER alone. When steady-state levels were regained after co-perfusion, perfusion of VER alone further potentiated glutamate release. The effect depended on the initial level of VER-induced glutamate release, and was maximum for intermediate glutamate levels. These results suggest that NO influences the glutamate release system by affecting the level of neural activity and that its effect lasts and increases when steady-state levels are regained in rat striatum.