Trichloroethylene: Free Radical Studies in B6C3F1 Mouse Liver Slices

Abstract : Electron paramagnetic resonance EPR/spin techniques were used to test the hypothesis exposure of liver to trichloroethylene (TCE) causes increased formation of free radicals. Precision cut liver slices from B6C3F1 mice were incubated for 20 min. with TCE at headspace concentrations ranging from 0-10,000, ppm with and without the spin trap N-tert-butyl-alpha-phenyl nitrone (PBN). PBN (10 mM) did not interfere with K + levels, lactate dehydrogenase, aspartamine transaminase or alanine transaminase. Free radicals were measured using Bruker ESP300E spectrometer. A solution of 3-carbamoyl-2,2,5,5,tetra methyl-1-yloxyl free radical was used as a standard to quantitate radicals. All data was normalized by liver wet weight. Total radicals increased linearly with increasing TCE headspace concentration (TR= (4.9E-04TCE +6.84) X 10E14, r=0.99 P <0.001). EPR/spin trapping results were corroborated by conjugated diene measurements and analysis by gas chromatography.