Inui K, Saito H, Takano M, Okano T, Kitazawa S, Hori R
Biochim Biophys Acta. 1984 Jan 25;769(2):514-8. doi: 10.1016/0005-2736(84)90340-7.
Apical membrane vesicles were isolated from the confluent LLC-PK1 cells by nitrogen cavitation and Mg/EGTA precipitation methods. The specific activities of marker enzymes for apical membranes were enriched 8- to 18-fold relative to those in the homogenate. D-[3H]Glucose uptake into the vesicles was stimulated in the presence of Na+ gradient (overshoot phenomenon), and the values of apparent Km and Vmax for Na+-dependent component of D-glucose uptake were 0.3 mM and 5.8 nmol/mg protein per min, respectively.
通过氮气空化和Mg/EGTA沉淀法从汇合的LLC-PK1细胞中分离出顶端膜囊泡。相对于匀浆，顶端膜标记酶的比活性提高了8至18倍。在存在Na+梯度的情况下，囊泡对D-[3H]葡萄糖的摄取受到刺激（过冲现象），D-葡萄糖摄取的Na+依赖性成分的表观Km和Vmax值分别为0.3 mM和5.8 nmol/mg蛋白质每分钟。
