Depression is associated with CRF hypersecretion, and studies revealed that CRF mRNA has higher expression in the PVN of patients with depression and also found elevated CRF in the CSF of drug-free depressed patients [6,7] Several analogs of CRF exist in different species, and they include urocortin, sauvagine, and urotensin. Here, CRH is linked to major depressive disorder.