The disposition of polychlorinated biphenyls (PCBs) differs between germ-free and conventional mice.
Xueshu Li, Joe Jongpyo Lim, Kai Wang, Bhagwat Prasad, Deepak K Bhatt, Julia Yue Cui, Hans-Joachim Lehmler
Author Information
Xueshu Li: Department of Occupational and Environmental Health, University of Iowa, Iowa City, IA 52242, USA.
Joe Jongpyo Lim: Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98105, USA.
Kai Wang: Department of Biostatistics, University of Iowa, Iowa City, IA 52242, USA.
Bhagwat Prasad: Department of Pharmaceutics, University of Washington, Seattle, WA 98105, USA.
Deepak K Bhatt: Department of Pharmaceutics, University of Washington, Seattle, WA 98105, USA.
Julia Yue Cui: Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98105, USA.
Hans-Joachim Lehmler: Department of Occupational and Environmental Health, University of Iowa, Iowa City, IA 52242, USA. Electronic address: hans-joachim-lehmler@uiowa.edu.
The disposition of toxicants, such as polychlorinated biphenyls (PCBs), in germ-free (GF) vs. conventional (CV) mice has received little attention to date. Here, we investigate PCB levels in three-month-old female CV and GF mice exposed orally daily for 3 days to 0, 6, or 30 mg/kg body weight of the Fox River Mixture (FRM), an environmental PCB mixture. We euthanized animals 24 h after the final dose. PCB profiles in tissues differed from the FRM profile but were similar in tissues across all 4 PCB exposure groups. PCB levels in CV but not GF mice followed the difference in PCB dose. Importantly, PCB levels were higher in CV than GF mice exposed to the same dose. Hepatic cytochrome P450 enzyme or lipid levels did not explain these trends in PCB tissue levels. Thus, toxicity studies with CV and GF animals need to assess the toxicokinetics of the toxicant investigated. CAPSULE: PCB levels are typically higher in conventional than germ-free mice exposed to the same dose of PCBs.
