title: Absorption, metabolism and distribution of (14C)-O-methyldopa and (14C)-L-dopa after oral administration to rats.
abstract: 1 The absorption, tissue distribution, and metabolism of [(14)C]-O-methyldopa were compared with those of [(14)C]-L-DOPA after oral administration to rats.2 Total radioactivity in the plasma and brain of rats treated with [(14)C]-O-methyldopa was significantly higher (2 fold and 30-50 fold, respectively) than that of rats treated with [(14)C]-L-DOPA.3 Total radioactivity in the gut washings and intestinal tissue 2 h after oral administration was significantly higher in rats treated with [(14)C]-L-DOPA than in rats treated with [(14)C]-O-methyldopa. The reverse was observed in the stomach tissues.4 Peripheral metabolism of [(14)C]-O-methyldopa was much lower than that of [(14)C]-L-DOPA; the major metabolite of [(14)C]-O-methyldopa in the plasma is L-DOPA, whereas L-DOPA is mainly metabolized to phenylcarboxylic acids.
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001923:Brain Chemistry; D002250:Carbon Radioisotopes; D004295:Dihydroxyphenylalanine / Q000008:administration & dosage / Q000097:blood / Q000378:metabolism*; D007422:Intestines / Q000032:analysis; D008297:Male; D008750:Methyldopa / Q000008:administration & dosage / Q000097:blood / Q000378:metabolism*; D010648:Phenylacetates / Q000096:biosynthesis; D051381:Rats; D013270:Stomach / Q000032:analysis
chemical_list: D002250:Carbon Radioisotopes; D010648:Phenylacetates; D008750:Methyldopa; D004295:Dihydroxyphenylalanine