Figure 5.

Blocking STEP activation triggers immediate-early gene expression. A, SE stimulated FosB (left) and JunB (right) expression in the GCL but not in the hilus. FK506 injection (1 mg/kg, 15 min after pilocarpine injection) significantly increased SE-induced FosB and JunB expression in the hilus. Mice were killed 1.5 h after SE onset. Boxed regions are magnified and shown on the right. Arrows denote cells with immediate-early gene expression. B, Double labeling with FosB and STEP revealed that immediate-early gene expression occurred in STEP-positive hilar cells. C, Quantitative analysis of FosB- or JunB-positive cells in the hilus under the different treatment conditions. Data from six animals were examined for each condition and expressed as the mean ± SEM. **p < 0.01. Error bars indicate SEM. Scale bars: A, 100 μm (low-magnification image) and 25 μm (high-magnification image); B, 10 μm; C, 25 μm.