Does moclobemide stimulate melatonin synthesis as the other selective MAO-A inhibitors do?

  • G. F. Oxenkrug
  • P. J. Requintina
  • A. Yuwiler
Conference paper
Part of the Journal of Neural Transmission book series (NEURAL SUPPL, volume 32)


It has been reported that selective MAO-A inhibitors, clorgyline and brofaromine, but not the MAO-B inhibitors, deprenyl and pargyline, stimulated rat pineal melatonin synthesis in humans and animals. Recent studies, however, found no eflect of moclobemide, a selective MAO-A inhibitor, on human plasma melatonin levels.

Present study found that in vitro moclobemide produced very weak stimulation of rat pineal NAT activity. However, in vivo moclobemide induced a significant increase of rat pineal NAS and melatonin content, and a dramatic decrease of 5-HIAA content (HPLC-fluorimetric procedure). Moclobemide’s effect on melatonin and related indoles could be detected as early as 30 min after the injection and lasted, at least, for 2 h.

The possible reasons for discrepancies between human and animal data are discussed.


Melatonin Synthesis Pineal Melatonin BioI Psychiatry Weak Stimulation Melatonin Content 
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Copyright information

© Springer-Verlag 1990

Authors and Affiliations

  • G. F. Oxenkrug
    • 1
  • P. J. Requintina
    • 1
  • A. Yuwiler
    • 2
  1. 1.Department of Psychiatry, VAMCBrown UniversityDavis Park, ProvidenceUSA
  2. 2.University of California at Los Angeles/Brentwood, VAMCLos AngelesUSA

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