Metabolism of 2-methylnaphthalene in the rat in vivo. I. Identification of 2-naphthoylglycine.
Urine was collected from four female rats for 3 days after two subcutaneous injections with 0.3 mg of 2-methyl[8-14C]naphthalene per kg. Of the 14C injected, 55% was found in the urine. The urine was solvent-fractionated into a toluene fraction (4.9% of urine 14C), a chloroform fraction (11.7%), two ethyl acetate fractions (41.7%), and a methanol fraction (37.8%). Only about 3-5% of urine 14C appeared to be unchanged 2-methylnaphthalene. A major radioactive peak which was isolated from the chloroform fraction was further subdivided into three peaks by HPLC. These metabolites, which may be three isomeric dihydrodiols of 2-methylnaphthalene, represented 6-8% of urine 14C. The more polar fractions contained several radioactive peaks when examined by TLC. One of these peaks was hydrolyzed with base to glycine and a 14C-labeled material which was similar to 2-naphthoic acid by TLC and by HPLC. Mass spectrometry of this latter material and of the unhydrolyzed metabolite confirmed the presence of 2-naphthoic acid and 2-naphthoylglycine, respectively. In total, 2-naphthoylglycine accounted for 30-35% of urine 14C.
D000818:Animals; D005591:Chemical Fractionation; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D005260:Female; D005998:Glycine / Q000031:analogs & derivatives* / Q000652:urine; D007279:Injections, Subcutaneous; D009281:Naphthalenes / Q000008:administration & dosage / Q000378:metabolism* / Q000652:urine; D051381:Rats; D012997:Solvents
D009281:Naphthalenes; D012997:Solvents; C035300:2-naphthoylglycine; C030037:2-naphthoic acid; C027384:2-methylnaphthalene; D005998:Glycine