Peel S, Liddiard B
J Microsc. 1976 Mar;106(2):239-49. doi: 10.1111/j.1365-2818.1976.tb02404.x.
In the pregnant rat, killed at about mid gestation and 1 h after injection of tritiated thymidine, 40% of the cells in the epithelium lining the uterine lumen at the implantation site were labelled. Between implantation sites fewer than 20% of the surface epithelial cells were labelled. A series of rats was given tritiated thymidine on day 12 of pregnancy and killed at intervals in the next 30 h. A percentage labelled mitoses analysis of the epithelium between implantation sites (interconceptual) and within the implantation site (conceptual) showed that cells in either region spent 7 h in DNA synthesis and 1-5 h in the G2 + 1/2 MITOSIS PHASES. The epithelial cells in the conceptual region spent 1-5 h in the G1 + 1/2 MITOSIS PHASES WHEREAS CELLS IN INTERCONCEPTual regions spent at least 11-5 h in these phases. The average cycle times of cells in conceptual regions was 10 h: in interconceptual regions minimum cycle time was 20 h and the average appeared to be considerably longer. The grain count of the epithelial cells in the conceptual region was rapidly reduced during the 30 h after injection of tritiated thymidine suggesting successive rounds of cell division. In contrast the grain count distribution of cells in interconceptual regions changed only slowly during this time. The percentage of labelled epithelial cells was determined in the animals killed up to 30 h after injection of tritiated thymidine. In both conceptual and interconceptual regions these percentages increased initially as labelled cells produced labelled progeny. In the conceptual region the increase was not maintained after 7 h as cells initially in G1 divided to give unlabelled progeny. In the interconceptual region the increase in the percentage of labelled cells continued for 14 h; thereafter the percentage did not significantly alter. The interpretation of these results is discussed in relation to the differences in the kinetic characteristics of the epithelial cells in the two regions and in relation to the morphology of the epithelium lining the uterus during pregnancy.
在妊娠中期左右处死的怀孕大鼠中，注射氚标记胸腺嘧啶1小时后，着床部位子宫腔内衬上皮细胞中有40%被标记。在着床部位之间，少于20%的表面上皮细胞被标记。一系列怀孕大鼠在妊娠第12天给予氚标记胸腺嘧啶，并在接下来的30小时内每隔一段时间处死。对着床部位之间（概念间）和着床部位内（概念内）的上皮细胞进行标记有丝分裂百分比分析表明，任一区域的细胞在DNA合成中花费7小时，在G2 + 1/2有丝分裂期花费1 - 5小时。概念区域的上皮细胞在G1 + 1/2有丝分裂期花费1 - 5小时，而概念间区域的细胞在这些阶段至少花费11 - 5小时。概念区域细胞的平均周期时间为10小时：在概念间区域，最短周期时间为20小时，平均周期时间似乎长得多。注射氚标记胸腺嘧啶后的30小时内，概念区域上皮细胞的颗粒计数迅速减少，表明细胞连续进行分裂。相比之下，在此期间概念间区域细胞的颗粒计数分布变化缓慢。在注射氚标记胸腺嘧啶后长达30小时处死的动物中，测定标记上皮细胞的百分比。在概念区域和概念间区域，这些百分比最初都随着标记细胞产生标记后代而增加。在概念区域，7小时后这种增加没有持续，因为最初处于G1期的细胞分裂产生未标记的后代。在概念间区域，标记细胞百分比的增加持续了14小时；此后百分比没有显著变化。结合两个区域上皮细胞动力学特征的差异以及妊娠期间子宫内衬上皮的形态，对这些结果进行了讨论。
