CRHR1 and major depressive disorder: The analysis found that some important genes related to MDD, such as serine protein kinases(AKT)[16], serotonin receptors(5HT2A, HTR2C)[17], corticotrophin-releasing hormone receptor (Crhr1)[18], glutamate transporters (SCL1A2)[19], were targeted by miR-451a, miR-221-3p or/ and miR-34a-5p(data no shown).