The findings herein show that the activities of ChAT and ACh in the rats' brains in the saline treatment model group decreased significantly, compared with those of the sham‐operation group, while the activities of AChE increased significantly, which further prove that CCH can lead to the disorder of the central cholinergic system (Choi et al., 2011; Kumaran et al., 2008; Tanaka et al., 1996). This evidence concerns the gene ACHE and columnar cell hyperplasia of the breast.