Effects of 3-OM-dopa on monoamine metabolism in rat brain.
We studied the effects of 3-methoxy, 4-hydroxy-phenylalanine (3-OM-dopa) on monoamine turnover, L-3-4-dihydroxy-phenylalanine (L-dopa) reversal of catecholamine depletion induced by alpha-methyl-paratyrosine (alpha-MT), and the passage of L-dopa across the blood-brain barrier of the rat brain. 3-OM-dopa did not affect monoamine turnover but interfered with restoration of dopamine levels by L-dopa. In addition, systemic 3-OM-dopa decreased brain uptake of 14C-L-dopa. High 3-OM-dopa blood levels may interfere with the therapeutic response to L-dopa in parkinsonism.
D000818:Animals; D001812:Blood-Brain Barrier; D001921:Brain / Q000187:drug effects / Q000378:metabolism*; D002250:Carbon Radioisotopes; D004298:Dopamine / Q000378:metabolism; D007980:Levodopa / Q000378:metabolism* / Q000627:therapeutic use; D008297:Male; D008781:Methyltyrosines / Q000378:metabolism / Q000494:pharmacology*; D009638:Norepinephrine / Q000378:metabolism; D010300:Parkinson Disease / Q000188:drug therapy / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D014443:Tyrosine / Q000378:metabolism / Q000031:analogs & derivatives; D019805:alpha-Methyltyrosine
D002250:Carbon Radioisotopes; D008781:Methyltyrosines; D014443:Tyrosine; D007980:Levodopa; D019805:alpha-Methyltyrosine; C008404:3-methoxytyrosine; D004298:Dopamine; D009638:Norepinephrine