R Subunits After pre-TBI Drug Administration. Western blot analysis of GABA-A receptor subunits α1, α2, α3, and γ2 in the hippocampus 24 h post-TBI with either no drug (untreated), MK-801 (NMDA calcium blocker, 0.3 mg/kg), diltiazem (L-type VGCC antagonist, 5 mg/kg), or diazepam (GABA-A agonist, 5 mg/kg). Histograms of protein expression were measured in Relative Optical Density (ROD) proportions normalized against the mean sham OD for each individual blot. Each blot contained at least 2 sham and 1 injured untreated protein lanes. Tissue from the same sham and injured groups was used for comparison to each drug by ANOVA. Asterisks indicate significant differences based on factorial ANOVA; *p < .05, **p < .01. Error bars represent +/-SEM. A: MK-801 normalized alpha 1 expression, while diltiazem and diazepam significantly increased expression in both sham and injured animals. B: No alpha 2 injury effects or drug effects were found for MK-801 or diltiazem, although diazepam significantly increased alpha 2 expression in both sham and injured animals. C: MK-801 significantly decreased alpha 3 expression in sham but not injured animals, while diltiazem and diazepam significantly decreased expression in both sham and injured animals. D: Gamma 2 expression was normalized by all drug treatments.