BDNF and major depressive disorder: There is also evidence that ELS induced by maternal separation (MS), which causes depression-like behavior in rats and can be reversed with antidepressants, is associated with an increase in MeCP2 binding to the exon IV but not exon I of the BDNF promoter in the hippocampus, which elicits a negative regulation of BDNF expression that can be reversed by chronic antidepressant treatment with escitalopram [113,114].