Livesey G, Williams K E
Biochem J. 1981 Sep 15;198(3):581-6. doi: 10.1042/bj1980581.
The rates of pinocytic uptake of a number of small 125I-labelled simple proteins (insulin, ribonuclease A and lysozyme) by rat yolk sacs incubated in vitro were determined both before and after treating these proteins with reagents that are known to increase the rate of capture of 125I-labelled bovine serum albumin. Uptake of the untreated forms of all three proteins was extremely rapid, indicating that adsorptive pinocytosis is the principal mechanism by which yolk-sac cells capture these simple proteins, but these rates show no simple correlation with molecular charge. In contrast with albumin, the rates of uptake of treated proteins were either unchanged or lower than that of the corresponding untreated protein preparations; polymeric forms of 125I-labelled lysozyme larger than dimers were ingested at rates significantly lower than that of the monomer.
在体外培养的大鼠卵黄囊中，测定了多种小的125I标记的简单蛋白质（胰岛素、核糖核酸酶A和溶菌酶）的胞饮摄取率，测定时间分别在这些蛋白质用已知能提高125I标记的牛血清白蛋白摄取率的试剂处理之前和之后。所有三种蛋白质的未处理形式的摄取极其迅速，这表明吸附性胞饮是卵黄囊细胞捕获这些简单蛋白质的主要机制，但这些速率与分子电荷没有简单的相关性。与白蛋白相反，处理后蛋白质的摄取率要么不变，要么低于相应未处理蛋白质制剂的摄取率；大于二聚体的125I标记溶菌酶的聚合形式的摄取率明显低于单体的摄取率。
