Original Article
Copyright ©2011 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Apr 7, 2011; 17(13): 1718-1724
Published online Apr 7, 2011. doi: 10.3748/wjg.v17.i13.1718
Differential expression of Bcl-2 and Bax during gastric ischemia-reperfusion of rats
Wei-Li Qiao, Guang-Ming Wang, Yue Shi, Jin-Xia Wu, You-Jian Qi, Jian-Fu Zhang, Hong Sun, Chang-Dong Yan
Wei-Li Qiao, Guang-Ming Wang, Yue Shi, Jin-Xia Wu, You-Jian Qi, Jian-Fu Zhang, Hong Sun, Chang-Dong Yan, Department of Physiology, Xuzhou Medical College, 84 West Huaihai Road, Xuzhou 221002, Jiangsu Province, China
Author contributions: Qiao WL, Wang GM, Shi Y, Yan CD, Zhang JF, Wu JX, Qi YJ and Sun H designed the research; Qiao WL, Wang GM and Shi Y performed the research; Qiao WL, Wu JX and Qi YJ contributed new reagents/analytic tools; Qiao WL, Yan CD, Zhang JF and Sun H analyzed the data and were involved in editing the manuscript; Qiao WL and Yan CD wrote the paper.
Supported by grants from the National Natural Science Foundation of China, No. 30570671, the Natural Science Foundation of Jiangsu Province, No. BK2009088, the Natural Science Fund for Colleges and Universities in Jiangsu Province, No. 10KJB310015 and the Xuzhou Social Development Fund, No. XM08C062
Correspondence to: Chang-Dong Yan, MD, Professor, Director, Department of Physiology, Xuzhou Medical College, 84 West Huaihai Road, Xuzhou 221002, Jiangsu Province, China. yancd55@hotmail.com
Telephone: +86-516-83262105 Fax: +86-516-83262014
Received: October 31, 2010
Revised: December 21, 2010
Accepted: December 28, 2010
Published online: April 7, 2011
Abstract

AIM: To investigate expression of Bcl-2 and Bax in gastric ischemia-reperfusion (GI-R) and involvement of extracellular signal-regulated kinase (ERK) 1/2 activation.

METHODS: The GI-R model was established by ligature of the celiac artery for 30 min and reperfusion in Sprague-Dawley rats. Rats were assigned to groups in accordance with their evaluation period: control, 0, 0.5, 1, 3, 6, 24, 48, and 72 h. Expression and distribution of Bcl-2 and Bax proteins were analyzed by immunohistochemistry and western blotting in gastric tissue samples after sacrifice.

RESULTS: Compared with controls, the percentage of positive cells and protein levels of Bcl-2 decreased in the early phases of reperfusion, reached its minimum at 1 h (P < 0.05); it then increased, reaching its peak at 24 h of reperfusion (P < 0.05). The pattern of Bax expression was opposite to that of Bcl-2. Bax expression increased after reperfusion, with its peak at 1 h of reperfusion (P < 0.05), and then it decreased gradually to a minimum at 24 h after reperfusion (P < 0.05). On the other hand, inhibition of activation of ERK1/2 induced by PD98059, a specific upstream MEK inhibitor, had significant effects on Bcl-2 and Bax in GI-R. Compared with GI-R treatment only at 3 h of reperfusion, PD98059 reduced the number of Bcl-2 positive cells (0.58% of R3h group, P < 0.05) and Bcl-2 protein level (74% of R3h group, P < 0.05) but increased the number of Bax-positive cells (1.33-fold vs R3h group, P < 0.05) and Bax protein level (1.35-fold of R3h group, P < 0.05).

CONCLUSION: These results indicated that the Bcl-2 and Bax played a pivotal role in the gastric mucosal I-R injury and repair by activation of ERK1/2.

Keywords: Stomach, Ischemia-reperfusion, Bcl-2, Bax, Extracellular signal-regulated kinase 1/2