Effects of HO-1 overexpression on radiation-induced skin cell apoptosis. (A) Representative RT-PCR analysis of the apoptosis pathway genes in rat skin tissues of indicated groups. (B) Real-time PCR analysis of the apoptosis pathway genes in indicated groups (4 animals per group). mRNA levels are presented as means ± SEM (normalized to β-Actin). The men expression level in PBS-injected control group was arbitrarily set as 100%. (C) Quantification of mean TUNEL-positive cells/per field are expressed as mean ± SD. * P < 0.05; ** P < 0.01, compared with PBS-injected control group.