Neuronal plasticity and survival in mood disorders

Studies at the basic and clinical levels demonstrate that neuronal atrophy and cell death occur in response to stress and in the brains of depressed p atients. Although the mechanisms have vet to be fully elucidated progress h as been made in characterizing the signal transduction cascades that centra l neuronal atrophy and programmed cell death and that may be involved in th e action of antidepressant treatment. These pathways include the cyclic ade nosine monophosphate and neurotrophic factor signal transduction cascades. It is notable that these same pathways have been demonstrated to play a piv otal role in cellular models of neural plasticity. This over-lap of plastic ity and cell survival pathways, together with studies demonstrating that ne uronal activity enhances cell survival, suggests that neuronal atrophy and death could result from a disruption of the mechanisms underlying neural pl asticity. The role of these pathways and failure of neuronal plasticity in stress-related mood disorders are discussed, Biol Psychiatry 2000;48:732-73 9 (C) 2000 Society of Biological Psychiatry.