Some inconsistencies in the biogenic amine hypothesis of depression have arisen from clinical studies with L-dopa and L-tryptophan, the metabolic precursors of the amines. The evidence obtained from the studies of changes in cellular amine levels in depressed patients reported here suggests that the interactions between catecholamines and indoleamines, and possibly other "false transmitter" amines, need to be considered in reevaluating the role of biogenic amines in the affective disorders.Abstract Teaser