equivalent to ppara−/−mice and our observation with glucose homeostasis in P-A+ mice is consistent with others’ reports (ref. 14, 15). The cyp2a5−/− mice exhibited obvious glucose intolerance, which is consistent with our previous report that alcohol can induce hyperglycemia in cyp2a5−/− mice but not in cyp2a5+/+ mice (ref.11). However, we did not observe a blood glucose recovering in cyp2a5−/− mice within 2 h after an insulin injection. FGF21 can augment insulin activity to promote glucose uptake in adipocytes (ref. 36). Basal levels of serum FGF21 was higher in cyp2a5−/− mice than in cyp2a5+/+ mice. It needs further studies to address whether elevated FGF21 in cyp2a5−/− mice contributes to sustained reduction of blood glucose in response to insulin injection.
