Jost S P
Virchows Arch B Cell Pathol Incl Mol Pathol. 1986;51(1):65-70. doi: 10.1007/BF02899016.
Normal unstimulated urothelium of adult mice appears to be essentially quiescent, as demonstrated by an 3HTdR-pulse labelling index of 0.11%. There is no evidence that this labelling index may be artificially low. Results from continuous labelling experiments, where 3HTdR was supplied in the drinking water of mice for varying periods, render it possible that the urothelium satisfies its small renewal requirements via a low growth fraction of cycling cells. The remainder may consist of quiescent cells, which may be capable of resuming cell cycle progression when required, and of post-mitotic cells, which are incapable of further proliferation. There are three possible levels of adult urothelial proliferation with cell cycle times of about a) one year (if the urothelium is homogeneous and the growth fraction unity), b) three weeks (if the growth fraction is about 5%), and c) 15 h (when the urothelial cells are rapidly regenerating).
成年小鼠正常未受刺激的尿路上皮似乎基本处于静止状态，3HTdR脉冲标记指数为0.11%就证明了这一点。没有证据表明该标记指数可能人为偏低。在连续标记实验中，将3HTdR添加到小鼠饮用水中不同时间段，结果表明尿路上皮可能通过低比例的循环细胞来满足其少量的更新需求。其余部分可能由静止细胞组成，静止细胞在需要时可能能够恢复细胞周期进程，还有终末分化细胞，它们无法进一步增殖。成年尿路上皮增殖可能存在三种水平，细胞周期时间分别约为：a）一年（如果尿路上皮是均匀的且生长比例为100%），b）三周（如果生长比例约为5%），c）15小时（当尿路上皮细胞快速再生时）。
