THE FUNCTIONS OF PULMONARY EPITHELIAL CELLS AND THEIR SECRETIONS

细支气管克拉拉细胞的功能目前尚不清楚。 一般认为细胞是分泌的。使用分离的Clara细胞 从兔的肺中，我们已经证明了由 细支气管Clara细胞是一种免疫化学低分子量蛋白质 而且在组成上与子宫红蛋白相似，子宫红蛋白是子宫的主要分泌蛋白 子宫上皮。此外，我们还鉴定了 含有Clara细胞分泌物的细支气管和气管上皮 通过使用免疫金程序来识别蛋白质。大多数分泌性蛋白质 似乎定位于Clara细胞的分泌颗粒，尽管 大量存在于内质网中。低谷 分子量蛋白质似乎由三种主要的亚型组成， 它们的等电点不同。

The functions of the bronchiolar Clara cell are not known although it is generally believed that the cell is secretory. Using Clara cells isolated from the lungs of rabbits we have shown that the major protein secreted by bronchiolar Clara cells is a low molecular weight protein immunochemically and compositionally similar to uteroglobin, the major secretory protein of the uterine epithelium. In addition, we have identified cells of the bronchiolar and tracheal epithelium that contain the Clara cell secretory protein by using an immunogold procedure. Most of the secretory protein appears to be localized in the secretory granules of Clara cells although substantial amounts are located in the endoplasmic reticulum. The low molecular weight protein appears to consist of three major isoforms that differ in their isoelectric points.