ABSTRACT
The excretion of metabolites of acrolein in rat urine after single oral administration of 10 mg/kg was investigated. S-Carboxyethylmercapturic acid (S-carboxyethyl-N-acetyl-cysteine), or S-(propionic acid methyl ester)mercapturic acid, was found as the major metabolite. An unidentified metabolite was found in expired air. Acrylic acid and methyl acrylate are suggested as intermediates in the metabolism of acrolein.
Subject(s)
Acrolein/metabolism , Aldehydes/metabolism , Animals , Female , Methylation , Rats , Rats, Inbred StrainsABSTRACT
The determination of thiodiglycolic acid (TDGA) In urine by gas chromatography (GC) is described. The analytical procedure includes addition of internal standard (o-phthalic acid), ethyl acetate extraction, evaporation of the solvent and silylation of TDGA with N-trimethylsilyl-diethylamine in pyridine (1:1). The results are calculated from the ratio of TDGA and internal standard peak heights. The detection limit of the method is 10 mg/l and the coefficient of various is +/- 5%.
Subject(s)
Thioglycolates/urine , Vinyl Chloride/metabolism , Vinyl Compounds/metabolism , Chromatography, Gas/methods , HumansABSTRACT
In order to assess the process of oxidation and conjugation involved in biotransformation of vinyl chloride (VC), rats were exposed to 50, 200, 500, 1000 and 20,000 ppm inhaled VC. The rate of urinary excretion of thiodiglycollic acid (TDGA) after exposure to each investigated concentration of VC depends on the activity of microsomal monooxygenase. In general, higher levels of TDGA in urine were reflected by a more significant depression of non-protein sulfhydryl content in the liver of rats, whereas no changes were observed in those with inhibited activity of microsomal monooxygenase and depressed urinary levels of TDGA. The significance of alcohol dehydrogenase in the metabolism of low concentrations of VC has not been confirmed. Metabolism of VC in the range of 50--2 000 ppm is mediated by microsomal monooxygenase followed by conjugation with thiols.
Subject(s)
Liver/metabolism , Sulfhydryl Compounds/metabolism , Thioglycolates/urine , Vinyl Chloride/metabolism , Vinyl Compounds/metabolism , Alcohol Oxidoreductases/metabolism , Animals , Biotransformation , Cobalt/pharmacology , Glutathione Reductase/metabolism , Male , Oxygenases/metabolism , Phenobarbital/pharmacology , Rats , Vinyl Chloride/administration & dosageABSTRACT
The determination of benzoic, 3- and 4-methylbenzoic, and mandelic acids in urine by gas chromatography (G.C.) is presented. The analytical procedure includes: addition of internal standard (beta-naphthol), alkaline hydrolysis, ethyl ether extraction, evaporation of the solvent, and silylation of acids with Silyl-8 in pyridine (1:1). The results are calculated from ratios of the internal standard and determined metabolites peak surface areas. The coefficient of variation of the method in determination of mentioned acids is +/- 8%.
