Figure 2. Comparison of the dose-response curves of intrathecal midazolam, AP-5 (NMDA antagonist), YM872 (AMPA antagonist), midazolam plus AP-5, and midazolam plus YM872 on the tail flick latency expressed as the peak percentage maximum possible effect. Intrathecal dose is indicated as the percentage of ED⁵⁰. Each point presents the mean +/- SEM of eight animals.