The effects of nitric oxide on striatal serotoninergic transmission involve multiple targets: an in vivo microdialysis study in the awake rat

The role of endogenous nitric oxide (NO) in N-methyl-D-aspartate (NMDA)-induced modulation of serotonin (5-HT) release in the striatum of freely moving rats has been studied using microdialysis technique. NMDA-induced increase in 5-HT release was significantly inhibited by selective nitric oxide synthase (nNOS) inhibitor S-methylthiocitrulline (S-Me-TC), ONOO- scavenger L-cysteine (L-cys), and guanylate cyclase (GC) inhibitor 1H[1,2,4]oxadiazolo[4,3-a]quinoxalin-l-one (ODQ). These data suggest that modulation of 5-HT levels is linked to the formation of NO produced by NMDA receptor activation and that endogenously produced NO increases 5-FIT concentrations both by stimulating? formation of 3'-5'-cyclic monophosphate (cGMP) and conversion of ONOO-. 2004 Elsevier B.V. (C) All rights reserved.