Figure 6.

Reinstatement of alcohol seeking (i.e., responding on a previously alcohol-reinforced lever), induced by 0.6 mA footshock stress, in Wistar rats trained to self-administer alcohol, and then extinguished over 15 nonreinforced sessions, and modulation of this behavior by MTIP. No effect was found in genetically nonselected Wistar rats without a history of dependence (left group; n = 9–11 per dose). In contrast, a dose-dependent suppression (main treatment effect, p = 0.014) was seen in nonselected Wistars with a history of dependence (middle group; n = 7 per dose). A similar dose-dependent suppression was also observed in genetically selected, alcohol-preferring msP rats (right group; main treatment effect, p = 0.004; n = 7 per dose). Significant (p < 0.05) reinstatement after footshock stress versus extinguished responding (Ext) is indicated by the number sign (#). Significant suppression of stress-induced responding by MTIP (p < 0.05 and p < 0.001, respectively, on post hoc comparison) versus respective controls is indicated by asterisks (* and **). For detailed statistics, see Results. Error bars indicate SEM.