大白鼠肝实质细胞的分离及其DNA单链区与细胞年龄的关系

本文报告了一个分离同一个体中老年、青年肝实质细胞(Parenchy-mal cell)的方法,并利用S_1酶作探针研究了不同年龄肝实质细胞DNA的单链区多寡与细胞年龄的关系。 用胶原酶溶液灌注活体大白鼠肝脏得到游离肝实质细胞。用Percoll作密度梯度介质对同一个体大白鼠的肝实质细胞进行梯度离心分离,得到比重不同的两部分肝实质细胞。再用S_1酶分别降解不同比重肝实质细胞DNA中的单链区域。结果表明:比重较大的肝实质细胞DNA中所含的单链区较比重小的肝实质细胞DNA中的单链区为多。提示这种差异可能与肝实质细胞的年龄有关。用不同年龄大鼠的肝细胞作对比,也证明老年大白鼠肝实质细胞DNA的单链区较多。

SEPARATION OF RAT HEPATIC PARENCHYMAL CELLS AND THE RELATIONSHIP BETWEEN DNA SINGLE-STRANDED REGIONS AND THE AGE OF CELLS

The rat liver was perfused with collagenase and the parenchymal cells were obtained.Percoll was used to separate differently aged parenchymal cells of the same rat.Two fractions of cells with different specific gravity were obtained.The single-stranded regions in the DNA of these cells were probed by nuclease S1 The result indicated that more single-stranded regions were found in DNA of parenchymal cells with the higher specific gravity than those with the lower specific gravity.The abundance of single-stranded regions in DNA seemed to be closely correlated with both the age of individual rat and the age of parenchymal cells,and the parenchymal cells with higher specific gravity were probably the aged ones.