游离脂肪酸在胆固醇结石成核中的作用

Effect of free fatty acid on cholesterol nucleation inmodel bile

采用分光光度法，测定了软脂酸、油酸、亚油酸、花生四烯酸这四种游离脂肪酸（ＦＦＡ）在模拟胆汁中对胆固醇结晶生长曲线的影响，探讨它们在胆固醇结石成核过程中的作用。结果表明：软脂酸、油酸、亚油酸、花生四烯酸，从０．５～２０μｍｏｌ／ｍｌ的不同浓度，使模拟胆汁成核时间均明显减少，仅为对照组的３０％～７０％（Ｐ＜０．０５）。加入软脂酸３μｍｏｌ／ｍｌ以上使最终胆固醇结晶浓度显著增高（Ｐ＜０．０１），且随浓度增加有上升趋势。不饱和脂肪酸（油酸、亚油酸及花生四烯酸）的最终胆固醇结晶浓度均显著低于对照组。表明四种ＦＦＡ均表现出促成核活性。结果认为ＦＦＡ是胆汁内具有促成核活性的非蛋白成核因子，其含量增加可导致胆固醇结石的形成。

e studied the effect of free fatty acids on choles-terol nucleation in model bile with a sensitive cholesterolcrystal growth assay. Palmitic acid, oleic acid, linoleicacid and arachidonic acid were added to model biles inincreasing concentrations from 0. 5 to 20 umol/ml. Thenucleation time of model bile with free fatty acids de-creased to 30% ￣50% of control bile. The final crystalconcentration increased with higher concentrations ofpalmitic acid. However, we found a decrease in the finalcrystal concentration with the unsaturated fatty acid-soleic acid, linoleic acid and arachidonic acid. The in-crease in the maximum crystal growth rate was markedin the model biles as linoleic acid was added. These find-ings show the effect of non-protein fraction in biles ongallstone formation and support the view that free fattyacids are pro-nucleating factors.