Autoradiographic Studies on Regeneration of the Experimental Gastric Ulcer with ³H-Thymidine

Abstract

The present study was undertaken to investigate the mechanism of the regeneration of the gastric ulcer.
I. Autoradiographs of the experimental gastric erosion.
Rats and rabbits were used. The erosive lesions which consisted of only the differentiated glandular cells were obtained by stripping surgically the half zone of the upper side of the gastric mucosa (fundic area). The erosive lesions were examined by using ³H-thymidine-autoradiographic techniques. Two days after the experimental erosion, the glandular cells were labeled with ³H-thymidine, suggesting a change of the differentiated cells into the proliferative cells. Seven days later, the foveolar epitheliums became visible in the erosive lesions. The foveolar epitheliums seemed to be regenerated from the differentiated cells.
II. Autoradiographs of the experimental gastric ulcer.
Rats were used. A circular piece of the mucosa 5mm in diameter was removed from fundic raea of the stomach. The parts of these ulcerative lesions were examined by the autoradiograph with ³H-thymidine. Two days later, the glandular cells in the bottom of glands around the margin of the defect were labeled with ³H-thymidine. Three days later, newly generated glandular canals, in which these glandular cells were distinctly labeled, appeared in the bottom of the glands around the margin of the defect. Five days after the ulcer, these new canals were gradually spreaded into the bottom of the gastric ulcer.
III. Serial histologic sections of the experimental gastric ulcer.
Rats were used. A circular piece of the mucosa 5mm in diameter was removed from fundic area of the stomach. Then serial sections of the lesions were histologically examined (H-E staining). Five days later, the new glandular canals appeared in the region of the bottom of the glands around the margin of the ulcer. These canals were related to neither the superficial regenerative epitheliums nor the neck region of the glands around the margin of the ulcer, suggesting that the new canals were generated from the bottom of the glands around the margin of the mucosa.
These findings suggest that the regeneration of the gastric ulcer does not only occur in the epitheliums and the undifferentiated cells on the neck region of the glands but also does in the differentiated glandular cells at the bottom of the glands.