Effects of nitric oxide on gastric ulceration induced by nicotine and cold-restraint stress

Table 2 Changes of ulcer index and adhesion mucus content after quit nicotine intake alone or with chronic nitric oxide donor (NO) treatment

Experimental group	No. of rats with lesions	Ulcer index (mm)	Adhesion mucus content (μg/g wet glandular tissue)
A. No stress (unrestrained at 22 °C for 2 hours)
Tap water	2 (7)	0.03 ± 0.02	391 ± 39
Quit nicotine	3 (8)	0.04 ± 0.02	278 ± 29a
Quit nicotine + NO (chronic)	2 (7)	0.04 ± 0.03	386 ± 37
B. Stress (restrained at 4 °C for 2 hours)
Tap water	8 (8)c	6.2 ± 0.7d	190 ± 18d
Quit nicotine	8 (8)c	9.0 ± 0.9ad	142 ± 16c
Quit nicotine + NO (chronic)	7 (7)b	5.8 ± 0.8d	210 ± 19d

Values are mean ± SD. Number of rats in each group is shown in parentheses. Lesions: Only petechiae in stomach were seen with non-stressed condition. Both petechiae and haemorrhagic ulcer in stomach were observed in stressed condition. Tap water: Rats drank water as control. Quit nicotine: Rats drank nicotine (50 µg/ml) for 20 days, then, nicotine was replaced by water for another 10 days. Quit nicotine + NO (chronic): Rats drank nicotine (50 µg/ml) for 20 days, then, nicotine was replaced by water, and rats were given NO donor three times daily by oral gavages for 10 days before experiment.

^aP < 0.05 when compared to its own tap water control in A or B.

^bP < 0.05,

^cP < 0.01,

^dP < 0.001 when compared to the corresponding control in A.