Neurotrophins: possible role in affective disorders.

Various monoamine hypotheses of affective disorders have been unable to provide a complete explanation for the observed clinical findings. Recently Duman et al. (1997) have produced a molecular and cellular theory of depression which seems to be a worthy successor to these hypotheses. Whereas the earlier theories were unable to explain the time lag between antidepressant drug administration and lightening of affect, Duman's group pinpoints intracellular mechanisms, in the right time frame, which decrease or increase the generation of neurotrophic factors necessary for the survival of certain neurons, particularly in the hippocampus. This new concept may lead to novel therapeutic approaches. Copyright 2001 John Wiley & Sons, Ltd.