IN-VIVO STIMULATED DOPAMINE RELEASE IN THE NUCLEUS-ACCUMBENS - MODULATION BY THE PREFRONTAL CORTEX

In vivo voltammetry was used to measure stimulated dopamine (DA) relea se in the nucleus accumbens following 6-hydroxydopamine (6-OHDA) lesio ns of the medial prefrontal cortex (PFC). Lesions of the PFC resulted in a significant potentiation of K+-stimulated DA release (383% of con trol). These data are in agreement with other studies which suggest DA ergic activation of cortical sites can alter the activity of DAergic n eurons at subcortical sites. Specifically these results suggest that D Aergic nerve terminals in the nucleus accumbens are tonically inhibite d by DAergic activity in the PFC and that alleviation of this tonic in hibition produces hyperresponsiveness in the nucleus accumbens.