Sister Chromatid Exchange Analysis in Cultured Primary Lung, Liver, and Kidney Cells of Mice Following in vivo Exposure to Vinyl Carbamate

Methods are described for the short-term culture (48 to 56 h) of lung, liver, and kidney cells from C57B1/6 mice. With these techniques, mice can be exposed in vivo to test compounds and the cells grown on cover glasses in the presence of 5-bromo-2' -deoxyuridine (BrdUrd) (5 µM) for analysis of sister chromatid exchange (SCE) and cell cycle kinetics. Mice exposed to vinyl carbamate (VC) ((10 to 60 mg/kg) by i.p. injection were used in the initial examination of this system. Cultured lung and kidney cells from exposed animals (60 mg/kg) exhibited significant increases in SCE frequencies (approximately 3 to 5 times baseline); however, liver cells were much less responsive and showed less than a twofold increase over baseline SCE levels. Lung cultures initiated as long as 320 h after VC exposure (60 mg/kg) revealed a persistence of lesions leading to the formation of SCEs in vitro. This methodology permits analysis of cytogenetic damage in organs with very low mitotic activity after in vivo exposure to known or suspected genotoxicants.