Evans M J, Johnson L V, Stephens R J, Freeman G
Lab Invest. 1976 Sep;35(3):246-57.
Rats were exposed to either NO2 or O3 to determine whether nonciliated cells (Clara cells) could divide and differentiate into ciliated cells in the terminal bronchioles. Dividing cells were labeled with tritiated thymidine, visualized in the light and electron microscopes using autoradiographic techniques, and studied for up to 15 days after labeling. Electron microscopic autoradiography 1 hour after injection of tritiated thymidine showed that all labeled cells in the terminal bronchioles were nonciliated. However, 4 days after injection of tritiated thymidine, 67.8 per cent of the labeled cells were nonciliated and 32.2 per cent were ciliated. Light microscopic autoradiography showed that the new labeled ciliated cell population was stable for up to 15 days. These results indicate that nonciliated cells divide and the sister cells may form new ciliated and nonciliated cells. Thus, nonciliated cells can act as progenitor cells for the terminal bronchiolar epithelium.
将大鼠暴露于二氧化氮或臭氧中，以确定无纤毛细胞（克拉拉细胞）是否能在终末细支气管中分裂并分化为纤毛细胞。用氚标记胸腺嘧啶核苷标记分裂细胞，利用放射自显影技术在光学显微镜和电子显微镜下观察，并在标记后长达15天进行研究。注射氚标记胸腺嘧啶核苷1小时后的电子显微镜放射自显影显示，终末细支气管中所有标记细胞均为无纤毛细胞。然而，注射氚标记胸腺嘧啶核苷4天后，67.8%的标记细胞为无纤毛细胞，32.2%为纤毛细胞。光学显微镜放射自显影显示，新标记的纤毛细胞群体在长达15天内保持稳定。这些结果表明，无纤毛细胞分裂，其姐妹细胞可能形成新的纤毛细胞和无纤毛细胞。因此，无纤毛细胞可作为终末细支气管上皮的祖细胞。
