Immunohistochemical study of dopamine in rat gastric mucosa with acute gastric ulcer.

Recent studies have shown the presence of dopamine (DA) in gastric and duodenal mucosa, and changes in gastric mucosal DA content have been observed in patient with acute ulcers. Immunohistochemical demonstration of the distribution of DA in gastric mucosa under stress was studied by light and electron microscopy. In the control group, DA was present in the gastric gland proper in the gastric corpus and antrum on light microscopy, and on the surface of mucous granules in chief cells, mucous neck cells, and surface epithelium on electron microscopy. In the stress group, DA in gastric mucosa was almost undetectable on light and electron microscopy. Further, in this group serum DA concentration was significantly higher in the portal vein than in the abdominal aorta. Endogenous DA in gastric mucosal cells may affect gastric mucosa differently from exogenous DA, and stress may release endogenous intracellular DA into extracellular spaces.