CRH and major depressive disorder: Similarly, in a rat model of IBS experiencing chronic unpredictable mild stress, EA treatment was shown to reduce the expression of both corticotropin-releasing factor (CRF) and CRF type 1 receptors in the hypothalamus, alleviate anxiety and depression, and reduce the expression of CRF type 1 receptors in the gastrointestinal mucosa, thus regulating tight junctions to repair the intestinal mucosal barrier.