Figure 7.

BI1029539 effect on seizure-induced up-regulation of P-gp and mPGES-1 levels in vivo. A) Western blot for P-gp and hmPGES-1 showing that kainic acid–induced SE increased P-gp protein expression levels in brain capillaries in vivo. This effect on P-gp was blocked by dosing hmPGES-1 mice with 10, 30, and 100 mg/kg BI1029539. SE also slightly increased hmPGES-1 protein levels in brain capillaries from hmPGES-1 mice; 10, 30, and 100 mg/kg BI1029539 blocked this effect as well. β-Actin was used as protein loading control. B) Representative images of brain capillaries isolated from hmPGES-1 mice after addition of NBD-CSA to determine P-gp transport function. Brain capillaries from mice that developed SE after kainic acid injection show increased luminal NBD-CSA accumulation compared with control mice. BI1029539 treatment blocked the SE effect and maintained luminal NBD-CSA fluorescence at control levels. Scale bar, 5 μm. C) Image analysis showed that specific luminal NBD-CSA fluorescence was increased in capillaries from SE animals indicating increased P-gp transport activity. No such increase was found in capillaries from SE animals that received BI1029539. For specific luminal NBD-CSA fluorescence, each data point represents the mean ± sem for 10 capillaries from pooled brain tissue of all mice per group (control n = 20, 100 mg/kg BI1029539 n = 20, kainic acid control n = 12, SE n = 16, SE + 10 mg/kg BI1029539 n = 20, SE + 30 mg/kg BI1029539 n = 17, SE + 100 mg/kg BI1029539 n = 22). Units are arbitrary units (au; scale: 0–255). ***P < 0.001, significantly higher than controls.