Studies on biliary and non-biliary pathways of cholesterol excretion and its regulation by food factors

我们试图建立一种比较胆固醇在大鼠胆汁和非胆汁排泄的实验方法。过夜禁食大鼠经胆汁排泄的胆固醇约为进食大鼠的2倍。禁食大鼠经非胆汁途径的胆固醇排泄量低于进食大鼠。给予LXR激动剂可增加非胆汁胆固醇排泄，但不增加胆汁胆固醇排泄。胆汁和非胆汁胆固醇排泄增加喂养高胆固醇饮食。胆汁和非胆汁胆固醇排泄的这些变化不能用ABCG5和ABCG8的mRNA表达来解释。因此，需要更多的研究来建立胆固醇通过胆汁和非胆汁途径排泄的调节机制。

We tried to establish an experimental method to compare biliary and non-biliary excretion of cholesterol in rats. Cholesterol excretion through bile in overnight fasting rats was about two times higher than that in the feeding rats. Cholesterol excretion through non-biliary pathway was lower in the fasting rats compared with the feeding rats. The administration of LXR agonist increased non-biliary cholesterol excretion, but not biliary cholesterol excretion. Both biliary and non-biliary cholesterol excretion were increased in the feeding of a high cholesterol diet. These changes in biliary and non-biliary cholesterol excretion could not be necessarily explained by the mRNA expression of ABCG5 and ABCG8. Therefore, more studies are necessary to establish mechanisms of the regulation of cholesterol excretion through biliary and non-biliary pathways.