Brief Reports
Copyright ©The Author(s) 2004. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Feb 15, 2004; 10(4): 594-597
Published online Feb 15, 2004. doi: 10.3748/wjg.v10.i4.594
Effects of nitric oxide on gastric ulceration induced by nicotine and cold-restraint stress
Bo-Sheng Qui, Qi-Bing Mei, Li Liu, Kam-Meng Tchou-Wong
Bo-Sheng Qui, Kam-Meng Tchou-Wong, Departments of Medicine, Environmental Medicine and Microbiology, New York University School of Medicine, New York, USA
Qi-Bing Mei, Li Liu, Department of Pharmacology, The Fourth Military Medical University, Xian, China
Author contributions: All authors contributed equally to the work.
Correspondence to: Dr. Kam-Meng Tchou-Wong, Departments of Medicine, Environmental Medicine, Microbiology, New York University School of Medicine, 550 First Avenue, MSB 141, New York, New York 10016, USA.
Telephone: +1-212-263-0243 Fax: +1-212-263-8902
Received: October 8, 2003
Revised: November 15, 2003
Accepted: December 24, 2003
Published online: February 15, 2004

AIM: Stress induces gastric ulceration in human and experimental animals. People tend to smoke more cigarettes when under stress. Nitric oxide (NO) and nicotine have opposing effects on gastric integrity. The present study examined the possible therapeutic benefit of NO in nicotine-treated rats with stress-induced gastric ulceration.

METHODS: Rats drank a nicotine solution while control rats drank tap water for 20 days. The alkoloid was then replaced by water with or without supplementation of isosorbide dinitrate (NO donor) for an additional 10 days. Isosorbide dinitrate was given twice shortly before experiments (acute) or three times daily by oral gavages for 10 days after the rats stopped drinking nicotine solution. At the end of experiments, ulcer index, gastric adhesion mucus content and MPO activity were measured and analysed.

RESULTS: Nicotine treatment decreased gastric mucus content and intensified stress-induced gastric ulcer. A higher ulcer index persisted even after the rats stopped drinking nicotine solution for 10 days. Acute NO donor showed no benefit on both mucus and ulcer index in nicotine treatment or/and stress condition. Chronic NO donor treatment reversed the worsening action of nicotine in stomach. Stress increased gastric mucosal myeloperoxidase (MPO) activity, which was antagonized by chronic NO treatment. However, nicotine was unlikely to change mucosal MPO activity.

CONCLUSION: The intensifying action of nicotine on stress-induced gastric ulceration persists for 10 days after cessation. Nicotine treatment significantly decreases gastric mucus content that can be restored by chronic NO donor treatment. The present study suggests that NO antagonizes the ulcerogenic action of nicotine through a cytoprotective way.

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