ACTA1 and columnar cell hyperplasia of the breast: As the ActA antagonist was administrated, the improvement of synaptic plasticity in CCH rats by enriching the environment was inhibited, suggesting that enriching the environment could improve the synaptic plasticity in CCH rats by activating Act A. However, we did not provided the hippocampus with zoom-in into the CAl area in Golgi staining and we will improve this issue in future investigations.