These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Comparison of neurochemical effects of the monoamine oxidase inhibitors phenelzine, moclobemide and brofaromine in the rat after short- and long-term administration.
    Author: Urichuk LJ, Allison K, Holt A, Greenshaw AJ, Baker GB.
    Journal: J Affect Disord; 2000 May; 58(2):135-44. PubMed ID: 10781703.
    Abstract:
    BACKGROUND: Chronic administration of several irreversible monoamine oxidase (MAO) inhibitors induces a down-regulation of tryptamine and 5-hydroxytryptamine(2) receptors in rat brain, but there is a paucity of information available on the effects of reversible MAO-A inhibitors on these receptors. METHODS: Acute and chronic experiments were conducted in rats and the effects of the irreversible monoamine oxidase inhibitor, phenelzine and the reversible MAO type-A inhibitors, moclobemide and brofaromine, on tryptamine and 5-hydroxytryptamine(2) receptors were analysed using radioligand binding techniques. In addition, activities of MAO-A and -B were determined radiochemically and brain and/or urine levels of tryptamine, 5-hydroxytryptamine, 3-methoxy-4-hydroxyphenylglycol (MHPG), beta-phenylethylamine, brofaromine and moclobemide were determined by chromatographic procedures. RESULTS: After 30 days of administration, moclobemide and brofaromine selectively inhibited brain MAO-A activity and phenelzine inhibited MAO-A and -B to equal extents. All three drugs caused a significant down-regulation of tryptamine receptors, whereas only phenelzine significantly down-regulated 5-hydroxytryptamine(2) receptors. In a comparison of phenelzine and brofaromine, both caused marked elevations of urinary tryptamine and decreases of urinary MHPG levels, while only phenelzine increased beta-phenylethylamine levels. After 14 days of administration, phenelzine, but not moclobemide or brofaromine, significantly increased levels of tryptamine in brain; all three drugs significantly increased 5-HT levels. LIMITATIONS: 24-h urine samples were not collected for moclobemide-treated animals and brain levels of tryptamine were not measured after 30-day administration. CONCLUSIONS: These studies revealed marked neurochemical differences among phenelzine, moclobemide and brofaromine which could contribute to their actions in the clinical setting.
    [Abstract] [Full Text] [Related] [New Search]