Figure 6.

μ-Opioid receptors in the NAc mediate social play-induced CPP. Intra-NAc infusion of CTAP prevented the development of social play-induced CPP in adolescent rats: animals infused with vehicle showed a significant preference for the compartment previously paired with social experience, whereas animals infused with CTAP (3 μg/0.3 μl) spent an equal amount of time in both the social- and non-social-paired compartments on the test day. Data represent mean ± SEM time spent in the social-paired (social, white bar) and non-social-paired (nonsocial, black bar) compartments on the test day. *p < 0.05 for difference in time spent in the social- and non-social-paired compartments (paired Student's t test; n = 6–7 per treatment group).