Figure 5
Self-administration of URB694 under FR10 schedule in anandamide-experienced squirrel monkeys. (a–c) Effects of varying injection doses on self-administration of URB694. Number of URB694 injections per 1 h session (a), overall rates of responding in the presence of the green light signaling drug availability (b), and total URB694 intake per session (c) are shown as a function of injection dose (abscissae log scale). The baseline responding for 30 μg/kg injections of anandamide is also shown. Each point represents the mean±SEM (n=4) of the last three sessions under each dose condition and under a vehicle (V) condition. *P<0.05; **p<0.01, post hoc vs the vehicle condition, Bonferroni test. (d, e) Acquisition of URB694 self-administration. Number of injections per session (d) and overall rates of responding (e) during anandamide (30 μg/kg/injection) self-administration (sessions 1–5), vehicle extinction (sessions 6–10), and URB694 (1 μg/kg/injection) self-administration (sessions 11–15) are shown. Points represent means±SEM (n=4). *P<0.05, **p<0.01, post hoc vs the mean of the last three sessions of anandamide self-administration (sessions 3–5); #p<0.05, ##p<0.01, post hoc vs the mean of the last three sessions of vehicle extinction (sessions 8–10), Bonferroni test. (f, g) Blockade of URB694 self-administration by pretreatment with rimonabant or MK886. Number of injections per session (f) and overall rates of responding (g) during URB694 (1 μg/kg/injection) self-administration are shown after IM pretreatment with vehicles (sessions 1–3 and 9–11), 1 mg/kg of rimonabant, or 1 mg/kg of MK886 (both sessions 4–8). Points represent means±SEM (n=4). *P<0.05, **p<0.01, post hoc vs the mean of the last three sessions of vehicle pretreatment (sessions 1–3), Bonferroni test.
