Fluorometric detection of 2-amino-3-methylimidazo[4,5-f]quinoline, 2-amino-3,4-dimethylimidazo[4,5-f]quinoline and their N-acetylated metabolites excreted by the rat.
A sensitive fluorometric method has been developed for the determination of carcinogenic amino imidazoazaarenes (AIA compounds) which are formed during the cooking of food. They are separated by t.l.c. followed by spraying with dimethylsulfoxide and visualization by long-wave u.v. light. Quantification is done by fluorescence scanning. This method was applied to the determination of the metabolites in urine and feces from rats given 5 mg/kg body wt i.p. of 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) and 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ). Metabolites extractable by organic solvents were identified as the parent compound and their N-acetylated derivatives (AcIQ, AcMeIQ). Between 0.1 and 1% of the administered dose was recovered as these metabolites in urine during 24 h. The amounts of MeIQ and AcMeIQ found in feces were approximately 1 and 3% respectively. AcIQ was not detected in feces while IQ, MeIQ and their N-acetylated derivatives were found in bile. The metabolites in urine were identified by m.s. and in feces by t.l.c. and their fluorescent properties. When IQ or MeIQ were incubated with rat liver cytosol in the presence of acetyl-CoA, N-acetylated derivatives were formed. The reverse reaction, deacetylation, also took place in the liver cytosol, with Km values of 67 and 32 microM for AcIQ and AcMeIQ respectively.
D000107:Acetylation; D000818:Animals; D003600:Cytosol / Q000032:analysis; D005470:Fluorometry; D008099:Liver / Q000032:analysis; D008297:Male; D009153:Mutagens / Q000032:analysis*; D011804:Quinolines / Q000032:analysis* / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D013056:Spectrophotometry, Ultraviolet
D009153:Mutagens; D011804:Quinolines; C029216:2-amino-3-methylimidazo(4,5-f)quinoline; C036989:2-amino-3,4-dimethylimidazo(4,5-f)quinoline