Fluorescent Histochemical Study on the Localization of Myofibroblasts in the Healing of Acetic Acid-Induced Gastric Ulcers in the Rat

The changes in the localization of FITC-phalloidin-positive smooth muscle cells and interstitial cells were studied in control and acetic acid-treated rat fundic mucosae. In the control rats, the FITC-phalloidin-positive cells mostly corresponded to smooth muscle cells of the muscularis mucosae, and arteriolar and venular smooth muscle cells. On the other hand, the fluorescence of the smooth muscle cells of the muscularis mucosae disappeared and a large number of fluorescent interstitial cells appeared in the regenerated mucosal layer in rats one week after the acetic acid-treatment, while three weeks after the application, severely thickened fluorescent muscularis mucosae were formed.