Fig. 2. Effects of pre-treatment with RTI-118 (A) or U69,593 (B) on cocaine-facilitated ICSS.

Abscissae: frequency of electrical brain stimulation in log Hz. Ordinates: percent maximum control reinforcement rate (%MCR). Pre-treatment doses of RTI-118 or U69,593 are indicated in legends in units of mg/kg. Filled points represent frequencies at which reinforcement rates were statistically different from vehicle + 10 mg/kg cocaine as determined by two-way ANOVA followed by Holm-Sidak post hoc test, P<0.05. All data show mean ± S.E.M. for five (RTI-118 + cocaine) or six (U69,593 + cocaine) rats.