title: The current status of monoamine oxidase and its inhibitors.
abstract: The enzyme monoamine oxidase (MAO) plays an important role in the inactivation of both dietary amines and also of neurotransmitter amines. A study of the properties of irreversible inhibitors of this enzyme suggests that the enzyme exists in two broad types--MAO-A and MAO-B. Although irreversible inhibitors of MAO were once widely used as antidepressant agents, they fell from favour because of adverse reactions after the ingestion of amine-containing foodstuffs ("the cheese reaction"). However, these inhibitors (phenelzine and tranylcypromine) are probably best for the treatment of atypical depression providing the patient is aware of dietary reactions. A new series of reversible, MAO-A selective inhibitors are being developed which do not exhibit serious dietary interactions. These reversible inhibitors show promise as rapidly acting antidepressant agents. An atypical irreversible MAO-B selective inhibitor, selegiline (deprenyl) does not exhibit an adverse reaction on the ingestion of amine-containing foods. This drug has been used as an adjuvant in the treatment of Parkinson's disease since it allows the dose of L-dopa to be reduced by approximately 25%. More important, selegiline may slow the degeneration of dopaminergic neurons that is characteristic of Parkinson's disease.
mesh_terms: D000499:Allylamine / Q000031:analogs & derivatives / Q000494:pharmacology / Q000627:therapeutic use; D001549:Benzamides / Q000494:pharmacology / Q000627:therapeutic use; D002986:Clinical Trials as Topic; D006801:Humans; D020912:Moclobemide; D008995:Monoamine Oxidase / Q000145:classification / Q000378:metabolism*; D008996:Monoamine Oxidase Inhibitors / Q000494:pharmacology / Q000627:therapeutic use*; D010080:Oxazoles / Q000494:pharmacology / Q000627:therapeutic use; D023303:Oxazolidinones; D012642:Selegiline / Q000494:pharmacology / Q000627:therapeutic use
chemical_list: D001549:Benzamides; D008996:Monoamine Oxidase Inhibitors; D010080:Oxazoles; D023303:Oxazolidinones; D012642:Selegiline; D000499:Allylamine; C040051:2-(3,4-dimethoxyphenyl)-3-fluoroallylamine; D008995:Monoamine Oxidase; D020912:Moclobemide; C026234:cimoxatone