Fig. 2.

Lack of effect of topiramate on cocaine discrimination. Data are means ± S.E.M of the percentage of responses on the lever associated with cocaine administration (upper panels) or rates of responding (lower panels) during the session. The discrimination performance of the rats is indicated in the upper panels Left panels: Topiramate administered alone (A, open symbols) did not produce cocaine-like discriminative effects. Topiramate administered in combination with the training dose of 10 mg/kg cocaine (A, filled symbols) did not alter the discrimination performance (A, open symbols). Topiramate alone (C, open symbols) or in combination with cocaine (C, filled symbols) did not affect rates of responding. Right panels: 10 or 30 mg/kg topiramate did not shift the dose-response curve for cocaine discrimination (B) and did not significantly decreased rates of responding of rats when given alone or in combination with cocaine (D). ED₅₀ values with 95% CIs for these dose-response curves are given in Table 1.