The purpose of this study was to assess the formation of chloramphenicol metabolites in primary turkey and rat hepatocyte cultures and human hepatoma (HepG2) cells and nonhepatic, Balb/c 3T3 fibroblasts. Additionally, the cytotoxicity of the drug was assessed through three biochemical endpoints: mitochondrial and lysosomal activity and cellular membrane integrity after 24 and 48 h exposure. The two metabolites of the drug, chloramphenicol glucuronide and nitroso-chloramphenicol, were detected to the greatest extent in both primary hepatocyte cultures by liquid chromatography-tandem mass spectrometry. Toxic nitroso-chloramphenicol was the main metabolite in the primary turkey hepatocyte cultures, but it was not in the primary rat hepatocyte cultures. The most affected endpoint in turkey and rat hepatocyte cultures was the disintegration of the cellular membrane, but in the cell lines, mitochondrial and lysosomal activities underwent the greatest change. The primary hepatocyte cultures represent valuable tools with which to study the species differences in the biotransformation and toxicity of drugs. To the best of our knowledge, this is the first report of differences in chloramphenicol metabolism in primary turkey and rat hepatocyte cultures.
Keywords: Balb/c 3T3 cell line; HPLC-MS/MS method; HepG2 cell line; chloramphenicol; cytotoxicity; metabolites; primary rat hepatocytes; primary turkey hepatocytes.