Study on the kinetics of mucus secreting cells in the gastrointestinal tract—Effects of various drugs and hormones on the cell kinetics of the generative zone in mouse gastric mucosa

The effects of various antiulcer drugs and hormones on the cell kinetics of the mouse gastric mucosa were studied using an autoradiographic technique with 3H-thymidine. The drugs or hormones were administered orally or parenterally once or twice a day for 7 consecutive days, and 3H-thymidine was injected after the last administration of the drug. The autoradiograph was prepared and then the labeling index was counted. Cimetidine (100 mg/kg × 2/day, p.o.), geranylgeranylacetone (GGA, 100 mg/kg × 2/day, p.o.), and Cu-chlorophyllin-Na (300 mg/kg × 2/day, p.o.) did not show any effect on the labeling indices in both the tissues of the fundic and pyloric glands, while carbenoxolone (100 mg/kg x 2/day, p.o.) reduced the labeling index in the pyloric glands. Tetragastrin (1 mg/kg × 1 /day, i.m.) increased the labeling index in the fundic glands, whereas secretin did not affect it. Hydrocortisone (100 mg/kg × 1/day, s.c.) reduced the labeling index in the fundic glands, and this reducing effect was prevented by combining hydrocortisone with GGA. From these results, it was indicated that the labeling index in the normal mouse gastric generative zone was not influenced by the tested antiulcer drugs, except carbenoxolone; but the index was influenced by tetragastrin and hydrocortisone, especially in the fundic glands. It was also suggested that the changes in the cell kinetics of the gastric mucosa could be related to the etiology of gastric ulcer since there was a possibility that geranylgeranylacetone could control the action of hydrocortisone, an ulcerogenic agent, on the gastric mucosal cell-cycle.