Chronic unpredictable stress (CUS) in rats was found to reduce gap junction function, the Cx43 immunoreactivity of gap junction aggregates and led to dramatic reductions in the expression of Cx43 and its mRNA that were preventable by treatment with glucocorticoid receptor antagonist mifepristone (Sun et al., 2012; Miguel-Hidalgo et al., 2019), also preventing the expression of depression-like behaviors. Here, GJA1 is linked to major depressive disorder.