Dopamine: mediator of brain polysome disaggregation after L-dopa.
The disaggregation of brain polysomes which is produced by giving large doses of (L)-dopa to rats is not reproduced by administering its metabolite, 3-O-methyldopa, by giving D-dopa, which also depletes the brain of S-adenosylmethionine but is not converted to catecholamines, or by giving the L-dopa after a decarboxylase inhibitor. Polysome disaggregation is potentiated by the prior administration of a monoamine oxidase inhibitor, indicating that formation of a catecholamine is an obligatory requirement. These observations suggest that the mechanism by which L-dopa disaggregates brain polysomes involves its conversion to dopamine within the majority of brain cells.
D000818:Animals; D001593:Benzyl Compounds / Q000494:pharmacology; D001921:Brain / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D001923:Brain Chemistry; D002262:Carboxy-Lyases / Q000037:antagonists & inhibitors; D004295:Dihydroxyphenylalanine / Q000008:administration & dosage / Q000032:analysis / Q000378:metabolism / Q000494:pharmacology*; D004298:Dopamine / Q000032:analysis / Q000494:pharmacology*; D006834:Hydrazines / Q000494:pharmacology; D007274:Injections, Intraperitoneal; D008297:Male; D008750:Methyldopa / Q000008:administration & dosage / Q000032:analysis / Q000494:pharmacology; D009638:Norepinephrine / Q000032:analysis / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D012270:Ribosomes / Q000187:drug effects*; D012436:S-Adenosylmethionine / Q000032:analysis; D012694:Serine / Q000494:pharmacology
D001593:Benzyl Compounds; D006834:Hydrazines; D012694:Serine; D008750:Methyldopa; D004295:Dihydroxyphenylalanine; D012436:S-Adenosylmethionine; D002262:Carboxy-Lyases; D004298:Dopamine; D009638:Norepinephrine