Expression of HDC and H~+, K~+-ATPase in gastric mucosa during the healing of acetic acid-induced gastric ulcer in rats

[Objective] To determine the expression change of histidine decarboxylase (HDC) and H+,K+-ATPase in gastric mucosa during the healing of acetic acid-induced gastric ulcer in rats. [Methods] Acetic acid-induced ulcers were caused by an application of acetic acid to the serosal surface of the anterior face of the rat gastric bodies. At different time points during ulcer healing, HDC and H+, K+-ATPase mRNA and protein expression were studied using reverse transcription-polymerase chain reaction and immunohistochemical staining, respectively. [Results] An ulcer crater developed on the anterior face of the gastric bodies after the induction of ulcers on day 1, and the ulcer area was biggest on day 3. By day 12, most of the gastric ulcers had healed. Compared with the control group, the HDC and H+, K+-ATPase mRNA expression in the gastric mucosa of ulcer rats showed a decrease on day 1, and increased back to the initial value on day 9. The percentage and the mean gray value of HDC and H+, K+-ATPase-positive cells in gastric mucosa of ulcer rats decreased immediately on day 1, most markedly on day 6, and returned to the initial levels on day 12. [Conclusion] The expressions of HDC and H+, K+-ATPase decrease in the healing process of gastric ulcers, probably resulting in accelerated ulcer healing through inhibiting gastric acid secretion.