Apoptosis in the cortex of the developing mouse kidney
Apoptosis in the cortex of the developing mouse kidney
复制标题
DOI：
10.1046/j.1469-7580.2002.00114.x
复制
发表时间：
2002-12-01
影响因子：
2.4
通讯作者：
Bard, JBL
中科院分区：
文献类型：
--
作者：
Foley, JGD;Bard, JBL
对于没有明显需要持续细胞死亡的组织来说，已发表的发育中大鼠肾脏的细胞凋亡水平（类似于 2.5%）似乎很大。本文研究了小鼠（标准哺乳动物模型胚胎）发育中肾皮质区域的细胞凋亡和有丝分裂的水平和模式。使用共聚焦显微镜对用碘化丙啶染色的标本突出显示核形态，分析深度接近50μm的整体肾脏的光学切片，并对各个区室中的有丝分裂、凋亡和间期细胞核进行计数。在 E11.5-16.5 期间检查的类似 200 000 个细胞中，2-3% 存在有丝分裂，证实了基于冷冻切片的观察结果；有丝分裂指数在E14.5处达到峰值，到P14时下降到大约0.5%。该时期平均细胞凋亡指数为0.28%；来自整体的这一数字与之前报道的冷冻切片大鼠肾脏的 10% 相似。对于这种差异的一种可能的解释是，冷冻切片产生了可以用丙啶强烈染色的小核碎片。此类片段在整体中看不到，并且不会用 TUNEL 染色。还分析了整体小鼠 E11.5 尾巴和 E16.5 肺，它们的有丝分裂和细胞凋亡指数与整体发育肾脏中的相似。这些结果表明，全胚胎小鼠肾皮质中的细胞凋亡水平远低于先前报道的冷冻切片大鼠胚胎肾中的细胞凋亡水平，并且是发育似乎不需要细胞凋亡的其他小鼠胚胎组织中的典型细胞凋亡水平。
Published levels of apoptosis in developing rat kidney (similar to2.5%) seem large for a tissue with no obvious need for continual cell death. This paper examines the levels and patterns of apoptosis and mitosis in the cortical region of the developing metanephros of the mouse, the standard mammalian model embryo. Using confocal microscopy on specimens stained with propidium iodide to highlight nuclear morphology, optical sections of wholemount kidneys to a depth of similar to50 lam were analysed and mitotic, apoptotic and interphase nuclei counted in the various compartments. Of the similar to200 000 cells examined over E11.5-16.5, 2-3% were mitotic, confirming observations based on cryosections; the mitotic index peaked at E14.5, dropping to similar to0.5% by P14. The mean apoptotic index during this period was 0.28%; this figure from wholemounts was similar to10% of that earlier reported in cryosectioned rat kidneys. One possible explanation for the difference is that cryosectioning turns out to create small nuclear fragments that can stain strongly with propidium. Such fragments are not seen in wholemounts and do not stain with TUNEL. Wholemount mouse E11.5 tails and E16.5 lungs were also analysed and both their mitotic and their apoptotic indexes were similar to those in wholemount developing kidneys. These results show that the level of apoptosis in wholemount embryonic mouse kidney cortex is far less than previously reported in cryosectioned rat embryonic kidneys, and typical of that in other mouse embryonic tissues whose development seems not to require apoptosis.