Morphologic evaluation of gastric mucosal protection by colloidal bismuth subcitrate (De-Nol).

The morphologic changes in the gastric mucosa of rats receiving colloidal bismuth subscitrate (CBS) at 120 mg/kg p.o. followed by intragastric instillation of 1 ml absolute ethanol have been assessed by macroscopic examination, quantitative histology and scanning electron microscopy. Macroscopically, virtually complete protection against ethanol injury was noted in CBS-pretreated animals, while control animals showed severe necrotic haemorrhagic lesions. Although light microscopy revealed disruption of the epithelium extending into the gastric pits, CBS protected deep pit cells and necrotic lesions were almost absent. By 6 h after ethanol instillation, surface epithelium was mostly restituted in the CBS group but not in the controls. Scanning electron microscopy (SEM) confirmed these findings. It is concluded that CBS protects the gastric mucosa against ethanol injury by preventing deep mucosal necrosis and that as a consequence the recovery of mucosal integrity is promoted.