Immunohistochemistry for cleaved caspase-3 was done as explained next [6 (link),17 (link)]. The sections were treated with rabbit anticleaved caspase-3 antibody (1:500; Cell Signaling Technology, Inc.) during overnight, and then incubated with biotinylated rabbit secondary antibody (1:200; Vector Laboratories) for another 1 hour. After amplification of the secondary antibody with the Vector Elite ABC kit (1:100; Vector Laboratories), 0.03% diaminobenzidine was used to visualized the antibodybiotin-avidin-peroxidase complex.