Morphological support for paracrine inhibition of gastric acid secretion by nitric oxide in humans.

BACKGROUND

Functional studies have shown that nitric oxide (NO) inhibits gastric acid secretion in a variety of species, including man. We have performed a morphological study with the intention of localizing the endothelial NO synthase (eNOS) in the human gastric mucosa.

METHODS

Fifteen healthy subjects voluntarily participated in the study, and mucosal biopsies were obtained from the cardia, corpus and antrum. The presence and localization of eNOS were studied using immunohistochemical techniques.

RESULTS

eNOS-immunoreactivity (eNOS-IR) is found in surface mucous cells of cardia, corpus and antrum. Unique to the oxyntic mucosa is the presence of eNOS-IR in 'endocrine-like' cells, found in close contact with parietal cells.

CONCLUSIONS

eNOS-IR cells in close apposition to parietal cells provide morphological support for paracrine inhibition of gastric acid secretion by NO.