Modification of L-DOPA pharmacological activity by MAO inhibitors

J Neural Transm (Vienna). 2007;114(6):801-5. doi: 10.1007/s00702-007-0691-y. Epub 2007 Apr 10.

Abstract

Dopamine behaves mainly as a MAO-A substrate in rodent brain, but selective inhibition of MAO-B results in an increased turning activity following L-DOPA administration in hemi-Parkinsonian rodents. Unilateral substantia nigra dopaminergic denervation results in serotonergic hyper-innervation which may increase the contribution of MAO-A in the denervated striatum. Possibly as a result of this, there was no change in striatal MAO-A activity when 95% of dopaminergic innervation was reduced by 6-hydroxydopamine, as assessed by apomorphine-induced turning activity. MAO-B as well as MAO-A may contribute to deamination of dopamine produced from L-DOPA.

MeSH terms

  • Animals
  • Basal Ganglia / drug effects
  • Basal Ganglia / enzymology
  • Basal Ganglia / physiopathology
  • Brain / drug effects*
  • Brain / enzymology*
  • Brain / physiopathology
  • Denervation
  • Dopamine / metabolism
  • Drug Interactions
  • Levodopa / pharmacology*
  • Monoamine Oxidase / drug effects
  • Monoamine Oxidase / metabolism
  • Monoamine Oxidase Inhibitors / pharmacology*
  • Neural Pathways / drug effects
  • Neural Pathways / enzymology
  • Neural Pathways / physiopathology
  • Oxidopamine
  • Parkinsonian Disorders / drug therapy*
  • Parkinsonian Disorders / enzymology*
  • Parkinsonian Disorders / physiopathology
  • Rats
  • Rats, Sprague-Dawley
  • Serotonin / metabolism
  • Substantia Nigra / drug effects
  • Substantia Nigra / enzymology
  • Substantia Nigra / physiopathology
  • Synaptic Transmission / drug effects
  • Synaptic Transmission / physiology

Substances

  • Monoamine Oxidase Inhibitors
  • Serotonin
  • Levodopa
  • Oxidopamine
  • Monoamine Oxidase
  • Dopamine