脂质体(ApoA-l:PC)的制备鉴定和功能研究

Preparation, Identification and Functional Studies on Liposome (ApoA-l:PC)

用脱氧胆酸透析法制备成功脂质体(ApoA-l:PC),并经琼脂糖凝胶电泳、双相薄层层析及电子显微镜鉴定。氨基黑10B染色呈一条区带,油红O染色阴性,双相薄层显示-棕黄色团,相当于磷脂酰胆硷位置,1％磷钨酸钠负染电镜下呈圆盘状粘着在一起,以上均显示脂质体由ApoA-l与PC组成。观察到脂质体加入量、LDL受体表达及胆固醇从细胞外流间的相关性,结果显示脂质体能增强受体表达作用,与脂质体能使细胞胆固醇外流有关。

Liposome (ApoA-1: PC) was prepared by the deoxycholic acid dialysismethod and identified by agarose gel electrophoresis, two demensional thin-layer chroma- tography and electron microscopy. The purified liposomes manifested one band in Amino black 10B staining and no color in Oil red O staining due to the presence of phospholipid. Only one brown spot appeared in two dimensional TLC, and electron microscopy with 1% sodium phosphotungstate negative staining revealed discoidal shapes stuck together. All of the above indicate that the liposome consisted of ApoA-1 and PC. Liposomes were added to the mediumof smooth muscle cell cultures and then LDL receptor expression and cholesterol efflux from the cells were observed. The results suggest that the ApoA-1:PC can enhance the expression of LDL receptors indirectly by stimulating cholesterol efflux from the cells.