To investigate the protective mechanism of probucol against cognitive impairments in CCH rats and to further explore the effect of probucol on hippocampal oxidative damage in CCH rats, we analyzed by western blot in the rat hippocampus of Syk, p-Syk, gp91phox, p47phox, and p22phox (Figure 3). This evidence concerns the gene SYK and columnar cell hyperplasia of the breast.