GJA1 and early-onset autosomal dominant Alzheimer disease: In contrast, in a mouse model proposed to mimic features of aging and Alzheimer’s disease induced by ovariectomy and chronic D-galactose administration, a reduction of Cx43 in the dentate gyrus and CA1 regions of the hippocampus was observed, while no change was observed in the CA3 hippocampal region (Liu et al., 2010).