title: Gentisuric acid: metabolic formation in animals and identification as a metabolite of aspirin in man.
abstract: Gentisuric acid was synthesized from gentisic acid and glycine ethyl ester. NMR, mass spectrometric and elemental analysis confirmed the product as GU, and physicochemical characteristics were determined. A TLC-densitometric technique was developed to estimate GU and other metabolites of aspirin. Conjugation of gentisic acid with glycine to form GU was catalyzed by a mitochondrial fraction of rat and beef liver. GU was also formed by the rat liver microsomal hydroxylation of salicyluric acid, and phenobarbital pretreatment increased this formation. A random survey showed GU in 76% of SA-positive urines from aspirin-treated patients. Identity of GU in urine from two aspirin-treated patients was confirmed by TLC and mass spectrometric analysis, and hydrolysis of the compound from one patient yielded glycine and gentisic acid. Urine from controls or post-aspirin treatment patients did not show GU by TLC analysis. These results demonstrate for the first time the metabolic formation of GU in animals and its occurrence as a metabolite of aspirin in man.
mesh_terms: D000217:Acyltransferases / Q000378:metabolism; D000328:Adult; D000818:Animals; D001241:Aspirin / Q000378:metabolism*; D002417:Cattle; D002849:Chromatography, Gas; D002855:Chromatography, Thin Layer; D005841:Gentisates / Q000138:chemical synthesis / Q000378:metabolism*; D005998:Glycine / Q000031:analogs & derivatives / Q000138:chemical synthesis / Q000378:metabolism; D000882:Haplorhini; D006801:Humans; D066298:In Vitro Techniques; D008099:Liver / Q000378:metabolism; D008297:Male; D013058:Mass Spectrometry; D006899:Mixed Function Oxygenases / Q000378:metabolism; D011817:Rabbits; D051381:Rats
chemical_list: D005841:Gentisates; D006899:Mixed Function Oxygenases; D000217:Acyltransferases; D001241:Aspirin; D005998:Glycine