Cell renewal in the eustachian tube epithelium of guinea pigs.

The turnover time of the epithelial cells of a normal eustachian tube was estimated in guinea pigs by means of lightmicroscopic autoradiography with thymidine-H3. The cell migration from the basal layer to the tubal lumen was chased by sacrificing the animals at different intervals after tnymidine-H administration. This study revealed that the generative cells were the basal cells in the tubal epithelium and that the different types of maturative cells in the epithelium have a different life span. The turnover time of non-ciliated secretory cells was about 145 hrs (about 6 days), while that of ciliated cells and goblet cells more than 6 days.