endogenous depression A mental depression that is characterized by a dysregulation of the endogenous opioid system and not of the monaminergic system. DOID:1595 DOID:6340 EFO:0003761 MSH:D003866 NCI:C34532 NCI:C35094 OMIM mapping confirmed by DO. [LS]. OMIM:608516 SNOMEDCT_2010_1_31:154873003 SNOMEDCT_2010_1_31:191599006 SNOMEDCT_2010_1_31:231498003 SNOMEDCT_2010_1_31:300706003 UMLS_CUI:C0011573 UMLS_CUI:C0041696 clinical depression disease_ontology unipolar depression mental depression