Gastric Cancer
Copyright ©The Author(s) 2005. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Aug 7, 2005; 11(29): 4457-4460
Published online Aug 7, 2005. doi: 10.3748/wjg.v11.i29.4457
Histological and ultrastructural changes induced by selenium in early experimental gastric carcinogenesis
Yan-Ping Su, Jun-Min Tang, Yan Tang, Hui-Ying Gao
Yan-Ping Su, Hui-Ying Gao, Department of Histology and Embryology, Taishan Medical College, Taian 271000, Shandong Province, China
Jun-Min Tang, Yan Tang, Department of Histology and Embryology, Peking University Health Science Center, Beijing 100083, China
Author contributions: All authors contributed equally to the work.
Supported by the Shandong Educational Office, No. J00K67
Correspondence to: Yan-Ping Su, Department of Histology and Embryology, Taishan Medical College, Taian 271000, Shandong Province, China. su-yanping@163.com
Telephone: +86-538-6222080
Received: October 23, 2004
Revised: December 23, 2004
Accepted: December 26, 2004
Published online: August 7, 2005
Abstract

AIM: To investigate the effect and significance of selenium in early experimental gastric carcinogenesis.

METHODS: Weaning male Wistar rats were divided randomly into normal control group, experiment control group, low selenium (2 mg/L) group and high selenium (4 mg/L) group. Wistar rat gastric carcinogenesis was induced by N-methyl-N-nitro-N-nitroso guanidine (MNNG) (20 mg/kg) gavage daily for 10 d. Na2SeO3 was given by piped drinking 1 wk prior to MNNG gavage. The rats were killed at the 43rd wk. The surface characteristics of gastric mucosa were observed with naked eyes. Histopathologic changes of rat gastric mucosa were observed by HE staining and AB-PAS methods. The changes of cellular ultrastructure were observed under transmission electron microscope. Statistical analysis was carried out by SPSS.

RESULTS: The incidence rate of gastric mucosa erosion, hemorrhage and intestinal metaplasia was 0, 45.5%, 66.7%, and 92.9%, respectively (92.9% vs 45.5%, P<0.05) in the normal control group, experiment control group, low selenium group, and high selenium group. Leiomyoma formed in the process of inducement of rat gastric carcinoma. Dietary Na2SeO3 (2 and 4 mg/L) slightly increased the incidence rate of leiomyoma (0, 23%, 46.6%, and 46.6%). gastric mucosa did not change in the course of rat gastric carcinogenesis. Dietary Na2SeO3 by pipe drinking could expand the intracellular secretory canaliculus of parietal cells and increase the number of endocrine cells and lysosomes.

CONCLUSION: Dietary Na2SeO3 by pipe drinking aggravates gastric erosion, hemorrhage and promotes intestinal metaplasia of gastric mucosa. The mechanism may be related with the function of parietal cells.

Keywords: Selenium; Ultrastructure; Experimental gastric carcinogenesis