Regulation of intracerebral gene expression for apoptotic mediators. Total RNA was extracted from homogenized murine brains (injured left hemispheres) at 4 h, 24 h, and 7 days after sham surgery or experimental head injury. Gene expression levels of Fas, FasL, Bax and Bcl-2 were determined by semi-quantitative two-step real-time RT-PCR, as described in the methods section. A significant induction of Fas gene expression was detected at 4 h in both trauma groups, compared to sham-operated controls (*P < 0.05, unpaired Student's t-test). In addition, head-injured wild-type mice showed a significant induction of Bcl-2 expression at all time-points after trauma, compared to sham-operated controls (*P < 0.05). No significant differences between head-injured wild-type and CD59a-/- mice were detected for any gene at any time-point. Data are shown as mean ± SEM for n = 6 per group and time-point. TBI, traumatic brain injury; WT, wild-type.