Sub-second changes in accumbal dopamine during sexual behavior in male rats

Transient (200-900 ms), high concentrations (200-500 nM) of dopamine, measu red using fast-scan cyclic voltammetry, occurred in the nucleus accumbens c ore of male rats at the presentation of a receptive female. Additional dopa mine signals were observed during subsequent approach behavior. Background- subtracted cyclic voltammograms of the naturally-evoked signals matched tho se of electrically-evoked dopamine measured at the same recording sites, Ad ministration of nomifensine amplified natural and evoked dopamine release, and increased the frequency of detectable signals. While gradual changes in dopamine concentration during sexual behavior have been well established, these findings dramatically improve the time resolution. The observed dopam ine transients, probably resulting from neuronal burst firing, represent th e first direct correlation of dopamine with sexual behavior on a sub-second time scale. NeuroReport 12:2549-2552 (C) 2001 Lippincott Williams & Wilkin s.