Comparison in changes of glutamate level in the rat nucleus accumbens induced by D1- and D2-dopamine receptors during feeding

The influence of dopamine D1- and D2-like receptors blockage on glutamate level in the n. accumbens of Sprague-Dawly rats during feeding was investigated by in vivo microdialysis combined with HPLC-EC analysis. Food intake resulted in a decrease in extracellular glutamate level. Infusion of D1-like dopamine receptor-blocker (SCH-23390, 0.01 mM) into the n. accumbens did not change this effect. Infusion of D2-like dopamine receptor-blocker (raclopride, 0.1 mM) into the n. accumbens caused an increase in extracellular glutamate level during feeding. The findings suggest, that decrease in extracellular glutamate level in n. accumbens is caused by dopamine D2-like, but not D1-like receptors activation.