Alteration of BA concentrations by PFNA in liver of WT, PPARα-null, and CAR-null mice. The liver concentrations of (A) CA, MCA, CDCA, UDCA, and DCA, as well as (B) individual unconjugated BAs, glycine-conjugated BAs, taurine-conjugated BAs, and total liver BAs were quantified by an UPLC-MS/MS method. The data are presented as mean ± SEM. Asterisks (*) represent a statistical difference (p < .05) between control and PFNA exposure. Single daggers (†) represent a statistical difference (p < .05) between WT and PPARα-null/CAR-null mice.