Fig. 4.

Accumbal dopamine during operant ethanol or sucrose self-administration. (A) Dialysate dopamine from the nucleus accumbens core–shell border during the wait, drink, and postdrink periods on the second day of exposure to ethanol (n = 10) and corresponding sucrose controls (n = 8). The arrow indicates the time during which the animal had access to the lever. Mean ± standard error of the mean are shown. The asterisk indicates a significant increase P < .05 for dopamine during the first drink period, when compared with the wait period (new baseline). (B) Data collected from the first day of 10% ethanol plus 10% sucrose (n = 12) and the corresponding day for the 10% sucrose group (n = 10).