Properties of 3H-MPTP binding sites in human blood platelets.
Our study demonstrates that 3H-1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (3H-MPTP) specifically binds to platelet membrane sites in humans. This specific, high affinity and saturable binding has properties similar to those of 3H-MPTP binding to rat and monkey brain, with a higher affinity. Deprenyl, a specific inhibitor of MAO type B enzyme, was the most potent drug in displacing 3H-MPTP from platelet binding sites. Platelets are considered a good model for central aminergic neurons and are very rich with MAO enzymatic activity, exclusively of type B. Our findings support previous evidence indicating a correspondence between 3H-MPTP binding sites and MAO-B enzyme. Moreover the presence of 3H-MPTP binding sites on human platelets suggests the use of this peripheral tissue as a simple model to study at least partially the mechanisms of neurotoxic action of MPTP.
D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; D001665:Binding Sites / Q000187:drug effects; D001667:Binding, Competitive; D001792:Blood Platelets / Q000378:metabolism*; D006801:Humans; D008995:Monoamine Oxidase / Q000097:blood; D008996:Monoamine Oxidase Inhibitors / Q000097:blood; D011725:Pyridines / Q000097:blood*
D008996:Monoamine Oxidase Inhibitors; D011725:Pyridines; D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; D008995:Monoamine Oxidase