Comparison of levels of nitric oxide in gastric juice of smoker and non-smoker patients with dyspepsia

Epidemiologic studies have shown that smoking is a major factor in development of malignancies in various human tissues. Smoke from every cigarette contains more than 600 µg nitric oxide radical (NO°) in gas phase. As a result of oxidation of nitrogen in gradients of tobacco and likely atmospheric nitrogen, more than 100 µg NO° is released in cigarette smoke which goes over human palate directly and without any filtering. In this research, we studied levels of nitric oxide in gastric juice of smokers and non-smokers afflicted with active peptic ulcer. Among persons referred to gastroenterology clinic, 43 smoker patients (14 men and 29 women) with average age of 45/30±13/16 who were afflicted with active peptic ulcer were determined as the case group, 43 non-smokers (13 men and 30 women) without peptide ulcer with average age of 42/67±16/04 were determined as the first control group, 43 smokers (16 men and 27 women) without peptic ulcer, with an average age of 44/58±12/07, were determined as the second control group and 43 non-smokers (23 men and 40 women) with peptic ulcer, with an average age of 45/37±13/39, were determined as the third control group. Levels of nitric oxide in gastric juice in the four groups were assessed by means of Griess colorimetric method. Compared to control groups 1 and 3, levels of nitric oxide in the case group showed a meaningful increase (in both groups, P˂0/0001) while nitric oxide levels in gastric juice of the case group and control group 2 (smokers without active peptic ulcer) did not have any meaningful difference (p=0/656). The results of this study ascertain that damage to the gastric tissue is in direct relationship with toxic elements in cigarette smoke especially NO° radical. It is very likely that peroxynitrite radical (ONOO- ), which resulted from rapid reaction between NO° and O2°, is responsible for these injuries. ONOOis a powerful oxidant and nitrating element that can promote reactions of HO°, nitrosoniume (NO2°) and nitrogen dioxide.

Active peptic ulcer, cigarette smoking, nitric oxide, nitrosative stress.