Antagonism of P2X7 reduces cerebral edema after TBI.
(A) A single intravenous bolus of 50 mg/kg BBG provided 15 minutes prior to TBI, significantly reduced the development of cerebral edema at 24h post-TBI, as measured by brain water content. (B) A single intravenous bolus of 50–100 mg/kg BBG administered 0.5h after TBI significantly reduced cerebral edema at 24h post-TBI. (C) Administration of a single intravenous bolus of 50 mg/kg BBG reduced cerebral edema when administered 1h or 4h after injury. This effect was lost if post-treatment was delayed beyond 8h from the time of injury. (D) Prophylactic treatment with BBG in the drinking water for 7 days reduced edema at 24h post-TBI at a concentration of 25 mg/ml but not 10mg/ml. Comparisons within each hemisphere between different treatments groups were done using a one-way ANOVA followed by Dunnett's post-hoc test (*p<0.05, **p<0.01, ***p<0.001 vs. the ipsilateral hemisphere in sham-operated mice). No significant differences in cerebral edema were observed between groups in the contralateral hemisphere. Data are represented as the mean ± SEM from 5–6 mice/group.