人血清脂蛋白与胆固醇修饰的葡聚糖的相互作用

采用浊度法和高效液相色谱法研究了人血清低密度脂蛋白（LDL）和极低密度脂蛋白（VLDL）与胆固醇修饰的葡聚糖（CHD）的相互作用。浊度法研究结果表明，CHD与VLDL混合溶液的浊度大于CHD与LDL混俣溶液的浊度。CHD浓度和CHD链上胆固醇含量都对溶液的浊度产生影响。当CHD浓度为0．3mg/mL，CHD链上胆固醇含量为4个／100个糖环时，混合溶液的浊度可达到最大值，表明LDL或VLDL要的程度最大。Ca^2 对CHD与LDL或VLDL的相互作用没有影响。高效液相色谱的研究结果表明，CHD与LDL的结合使得复合物分子量增加；CHD分子量增大，复合物分子量也增加；当葡聚糖上胆固醇含量为4．0时，复合物分子量最大。实验结果表明，CHD能引起LDL或VLDL的自聚集。

The Interaction of Human Lipoprotein with Cholesterol Modified Dextran in Serum

The interaction of human low density lipoprotein(LDL) and very low density lipoprotein(VLDL) with cholesterol modified dextran(CHD) in serum was studied by turbidity and high performance liquid chromatography(HPLC)method. The solution turbidity of VLDL reacting with CHD was higher than that of LDL with CHD and was influenced by the concentration of CHD, cholesterol content of CHD and molecular weight of CHD . The turbidity reached the maximum value when the concentration of CHD was 0.3 mg/mL and cholesterol content was 4 cholesterol group/100 dextran glucose units. Ca 2+ had no influence on the interaction of VLDL and LDL with CHD.The molecular weights of LDL CHD complex were monitored by HPLC which showed that CHD molecules could associate multi molecules of LDL correlating with the results of turbidity experiments. The HPLC experiments showed that when cholesterol substitution number was 4/100 glucose units, the interaction of LDL with CHD reached the optimal condition and the complexation molecular weight increased with increasing dextran molecular weight. The experimental results show that CHD can induce self aggregation of LDL or VLDL.