DYNAMICS OF EPITHELIAL-CELLS IN THE CORPUS OF THE MOUSE STOMACH .5. BEHAVIOR OF ENTERO-ENDOCRINE AND CAVEOLATED CELLS - GENERAL CONCLUSIONSON CELL-KINETICS IN THE OXYNTIC EPITHELIUM

Entero-endocrine cells and the rare cells named caveolated or brush ce lls have been examined in light microscopic radioautographs of the mou se corpus after various periods of continuous H-3-thymidine infusion. Moreover a search for immature forms and mitoses of these cells was un dertaken in the electron microscope. Entero-endocrine cells are presen t in the four regions of the epithelial units, but their number is low in the pit, intermediate in the isthmus and neck, and high in the bas e. The labeling pattern after continuous H-3-thymidine infusion indica tes that these cells are produced in the isthmus from undifferentiated granule-free cells presumed to be the stem cells of the epithelium, a nd may retain a limited ability to divide. A few of the newly formed e ntero-endocrine cells migrate to the pit, but the majority goes to the neck and, from there, to the base where they are present in relativel y high numbers. Little information is available on the dynamics of cav eolated cells. Since immature forms are present in the isthmus and mat ure ones in the other regions, it is concluded that they arise in the isthmus and migrate away in both directions. Finally, concluding remar ks are presented on the kinetics of each one of the cell lineages desc ribed in this and the four previous articles.