[Action mechanism of antidepressive drugs. Review of current knowledge]

Although more than twenty-five years of clinical use and several placebo-controlled studies have demonstrated the clinical effectiveness of anti-depressant drugs, the mechanism through which these drugs function and how they relate to the pathological mechanisms that underlie depressive disorders are still not clear. The present article briefly reviews the literature available on the subject. In chronological order, it examines studies on the clinical effectiveness of antidepressants, their effects on biogenic amine metabolism and on known receptor systems. The existence of possible specific receptor systems for tricyclic anti-depressants, their modifications during depressive illness, the effect of treatment with psychotropic drugs and the role which these systems may play in depression are then illustrated.