Dynamic analysis of the stomach epithelium - 3H-thymidine autoradiographic study

Abstract

The cellular proliferation and differentiation of the stomach epithelium of the hamster were studied by the 3H-thymidine autoradiography. In comparison, autoradiographs of human materials, such as gastric cancer were analysed using “local labeling” of 3H-thymidine.The results obtained are as follows:1. The generative cell zone at the junction between the surface and the glandular epithelium of the hamster stomach was demonstrated by the 3H-thymidine autoradiography.The generative cells possess basophilic cytoplasm and ovoid large nuclei. The mitotic figures are frequent among these cells. Relative size of the nuclei of the generative cell is distributed between unity and two, reflecting their constant DNA sythesis and division. The generative cells are detected in the cardiac gland, the fundic gland and the pyloric gland. Some generative cells show positive PAS reaction. Two hours after injection of 3H-thymidine, labeling indices of the generative cells are 30, 25 and 30 percent in cardiac gland, in fundic gland and in pyloric gland, respectively.The labeling index of the PAS positive generative cells is lower than that of the other generative cells.2. By pursuit of the labeled cells with lapse of time, it is proved that the generative cells differentiate to the surface epithelium and the glandular cells.3. Chasing migration of the labeled cells the life span of the surface epithelium are estimated as 48 hours, 3 days and 3 days in cardiac, fundic and pyloric gland, respectively.4. By the cumulative labeling of 3H-thymidine the life span of the glandular cells were 3 days in cardiac gland. In fundic gland it is more than 21 days and in pyloric gland 7-10 days.5. The generation time of the generative cells are calculated about 25 hours in cardiac gland, 30 hours in fundic gland and 25 hours in pyloric gland.6. The surface epithelium, the generative cells and the glaudular cells in each portion of the stomach constitute respective cell compartment keeping constancy in cell numbers.7. The generative cell compartment plays an important role as source of differentiated cells. The bulk of the each cell compartment is kept constant on the balance which depends on both the generation time of the generative cells and the life span of the maturative cells. The maturative cells consist of the surface epithelium and the glandular cells.The tissue structure of the normal stomach epithelium perpetuates in spite of the constant renewal of the constituent cells. This is assured through the mechanism controlling the generation time of the generative cells and the life span of the maturative cells.8. By 3H-thymidine autoradiography after Polymixin B injection, labeling index of the generative cells increases distinctly than normal. The labeling index was 40-50 percent. Incorporation of 3H-thymidine is found in some parietal cells in fundic gland after the Polymixin B injection, but not in the surface epithelium and the other glandular cells.9. The local labeling technique of 3H-thymidine autoradiography is applied to human stomach epithelium by at time of the surgical operation. These materials include gastric ulcers and gastric cancers. The generative cell zone is found in the transitional portion between the surface epithelium and the glandular cells of the fundic gland and pyloric gland. The labeling index was about thirty percent.10. The generative cell compartment of the pyloric gland of the human stomach varies in size at different places. The glandular cells are absent in some portion of the pyloric gland replaced by the generative cells.11. The eroded lesion of the surface epithelium is later covered by the proliferating generative cells without the cellular differentiation. Therefore the generative cell zone was extended than in the normal state.