Basic Research
Copyright ©2006 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Jun 7, 2006; 12(21): 3368-3372
Published online Jun 7, 2006. doi: 10.3748/wjg.v12.i21.3368
Dynamic functional and ultrastructural changes of gastric parietal cells induced by water immersion-restraint stress in rats
Yu-Mei Li, Guo-Ming Lu, Xiao-Ping Zou, Zhao-Shen Li, Gui-Yong Peng, Dian-Chun Fang
Yu-Mei Li, Department of Gastroenterology, Hospital of Zhejiang Armed Police Forces Crops, Jiaxin 314000, Zhejiang Province, China
Guo-Ming Lu, Department of Pathology, Medical College, Jiaxing University, Jiaxing 314001, Zhejiang Province, China
Xiao-Ping Zou, Zhao-Shen Li, Department of Gastroenterology of Changhai Hospital, Second Military Medical University, Shanghai 200433, China
Gui-Yong Peng, Dian-Chun Fang, Department of Gastro-enterology of Southwest Hospital, Third Military Medical University, Chongqing 400038, China
Supported by the Key Project of Military Medicine during the 10th five-year Plan period, PLA, China, No. 01Z059
Correspondence to: Yu-Mei Li, Department of Gastroenterology, Hospital of Zhejiang Armed Police Forces Crops, Jiaxin 314000, Zhejiang Province, China. li.yumei@sohu.com
Telephone: +86-573-2852851-37537 Fax: +86-573-2852933
Received: February 24, 2005
Revised: February 28, 2005
Accepted: August 10, 2005
Published online: June 7, 2006
Abstract

AIM: To investigate the dynamic functional and ultrastructural changes of gastric parietal cells induced by water immersion-restraint stress (WRS) in rats.

METHODS: WRS model of Sprague-Dawley (SD) rats was established. Fifty-six male SD rats were randomly divided into control group, stress group and post-stress group. The stress group was divided into 1, 2 and 4 h stress subgroups. The post-stress group was divided into 24, 48 and 72 h subgroups. The pH value of gastric juice, ulcer index (UI) of gastric mucosa and H+, K+-ATPase activity of gastric parietal cells were measured. Ultrastructural change of parietal cells was observed under transmission electron microscope (TEM).

RESULTS: The pH value of gastric juice decreased time-dependently in stress group and increased in post-stress group. The H+, K+-ATPase activity of gastric parietal cells and the UI of gastric mucosa increased time-dependently in stress group and decreased in post-stress group. Compared to control group, the pH value decreased remarkably (P = 0.0001), the UI and H+, K+-ATPase activity increased significantly (P = 0.0001, P = 0.0174) in 4 h stress subgroup. UI was positively related with stress time (r = 0.9876, P < 0.01) but negatively with pH value (r = -0.8724, P < 0.05). The parietal cells became active in stress group, especially in 4 h stress subgroup, in which plenty of intracellular canalicular and mitochondria were observed under TEM. In post-stress group, the parietal cells recovered to resting state.

CONCOUSION: The acid secretion of parietal cells is consistent with their ultrastructural changes during the development and healing of stress ulcer induced by WRS and the degree of gastric mucosal lesions, suggesting gastric acid play an important role in the development of stress ulcer and is closely related with the recovery of gastric mucosal lesions induced by WRS.

Keywords: Stress ulcer, Gastric parietal cells, Ultrastructure, H+, K+-ATPase activity, Sprague-Dawley rat