Female, adult C57BL/6 mice were injected (i.p.) with vehicle (50% DMSO) or DFP in vehicle solution at specific dose levels (2, 3, or 4 mg/kg). Mouse behavior was characterized using a Modified Racine Seizure Inventory every 3 min for 15 min and recorded. The mice were sacrificed by focused microwave irradiation of the head at 15 min post-injection and brain tissue collected for phosphorylation state analysis. (Left panel) Mean seizure ratings are shown for each treatment group (N=5 mice/treatment condition). (Right panel) Mean levels of phospho-T75 DARPP-32 in mouse striatum are shown as a function of DFP treatment. Phospho-T75 DARPP-32 and total DARPP-32 levels were detected in striatal homogenates from individual mice by immunoblotting and antibody binding revealed using dual-channel fluorescence imaging using Li-Cor Odyssey software then normalized for total levels. Data are expressed as a percent ± SEM of levels in the brains of vehicle-treated control mice. (*p<0.05 compared with vehicle-injected controls, ANOVA with Newman-Keuls post-hoc test, n=5 mice/group).