Simultaneous in vivo voltammetric measurement of striatal extracellular DOPAC and 5-HIAA levels: effect of electrical stimulation of DA and 5-HT neuronal pathways.

Differential pulse voltammetry (DPV) combined with electrically pretreated carbon fibre electrodes has been used to study dopamine (DA)-5-hydroxytryptamine (5-HT) interactions in the striatum of anaesthetised rats. Electrical stimulation of the dorsal raphe (DRN) increased 5HT and decreased DA metabolism in the striatum. Conversely, stimulation of the DA pathway to the striatum was associated with increased DA and decreased 5-HT metabolism. These data support previous studies and demonstrate that there is a functional interaction between DA and 5-HT systems in the striatum. The receptors and other transmitters (if any) involved in this interaction remain to be determined.