BDNF and major depressive disorder: Notably, the main novelty of the present study is that NH induced very long-lasting enhancements of BDNF and PSA-NCAM levels in the PFC, ACg, and vHPC in two genetically selected strains, the RHA and RLA rats, which differ in their anxiety-related behaviour, coping style, stress hormone responses, attention and sensorimotor gating, cognition, and other neurobehavioural traits associated with vulnerability to stress/depression and schizophrenia-linked features [2,3,4,5,6,9,10,11,12,13,14,17,18,19,20,21].