CYP7A1 and heavy chain disease: The results demonstrated that a significant decrease in the expression level of hepatic cholesterol 7 alpha-hydroxylase (Cyp7a1), and there was no obvious difference in the expression of hepatic HMG-CoA reductase (Hmgcr), scavenger receptor-BI (Sr-bI), and the low-density lipoprotein receptor (Ldlr) in the HCD group compared with the CD group (Figure 5A).