Quirk S J, Byrne J, Robinson G B
Biochem J. 1973 Mar;132(3):501-8. doi: 10.1042/bj1320501.
The kinetics of incorporation of [(3)H]lysine and [(14)C]glucosamine into kidney brush borders were studied in vivo. The patterns of incorporation and loss of radioactivity from the brush borders were similar for both radioactively labelled precursors. Maximal labelling occurred 15-20h after injection of the precursors, and then the radioactivity declined rapidly until 50h. The radioactivity of brush borders then remained constant until 120h and thereafter declined slowly. These results are interpreted as indicating that two processes contribute to the turnover of brush-border components, pinocytosis and a slower turnover of the components of the microvilli. Studies of the distribution of radioactivity among glycoprotein components of the brush borders, separated by polyacrylamide-gel electrophoresis, indicated that the membrane components turned over in unison.
在体内研究了[³H]赖氨酸和[¹⁴C]葡糖胺掺入肾刷状缘的动力学。对于两种放射性标记的前体，刷状缘放射性掺入和损失的模式相似。在前体注射后15 - 20小时出现最大标记，然后放射性迅速下降直至50小时。此后刷状缘的放射性保持恒定直至120小时，之后缓慢下降。这些结果被解释为表明有两个过程导致刷状缘成分的周转，即胞饮作用和微绒毛成分较慢的周转。通过聚丙烯酰胺凝胶电泳分离对刷状缘糖蛋白成分中放射性分布的研究表明，膜成分同步周转。
