GJA1 and major depressive disorder: As mentioned above, a number of previous pharmacological studies suggested that the functional abnormalities of astroglial transmission associated with Cx43 contributed to the pathophysiology/pathomechanisms of mood disorders; however, the functional abnormality of Cx43 associated with mood disorders is more complicated than expected, as the findings regarding Cx43 expression and the functions of the abnormalities in depression models and the effects of the 5-HT transporter inhibiting antidepressants are inconsistent [33,34,35,36,37,38,39,40,41].