Ma L, Wang W P, Chow J Y, Lam S K, Cho C H
Department of Pharmacology, Faculty of Medicine, University of Hong Kong, China.
Gut. 2000 Aug;47(2):170-7. doi: 10.1136/gut.47.2.170.
Cigarette smoking was shown to delay gastric ulcer healing and reduce synthesis of mucus, which is important for gastric ulcer protection and healing. Polyamines are important in these processes.
To study the effects of cigarette smoking on the synthesis of mucus and to investigate if such an effect is acting by interference with the polyamine pathway.
Gastric mucosal ornithine decarboxylase activity, mucous secreting layer thickness, and ulcer size were determined after different concentrations of cigarette smoke exposure (0, 2, or 4%) in intact animals and animals with ulcers. Synthesis of mucus and ornithine decarboxylase activity and mRNA expression were also assessed in cigarette smoke extract treated MKN-28 cells.
Exposure to cigarette smoke significantly reduced the thickness of the mucous secreting layer and gastric mucosal ornithine decarboxylase activity in animals with or without ulcers. Spermidine not only reversed inhibition of mucus synthesis in both intact and ulcer bearing animals but also reversed the delay in ulcer healing. Cigarette smoke extract significantly reduced mucus synthesis and ornithine decarboxylase activity but not its mRNA expression in MKN-28 cells. The reduction in mucus synthesis was restored by spermidine.
Cigarette smoke and its extract repress mucus synthesis in vivo and in vitro, respectively. Reduction of ornithine decarboxylase activity in gastric mucosa is closely associated with this effect.
研究表明，吸烟会延迟胃溃疡愈合，并减少黏液合成，而黏液对胃溃疡的保护和愈合至关重要。多胺在这些过程中起着重要作用。
研究吸烟对黏液合成的影响，并探讨这种影响是否通过干扰多胺途径起作用。
在完整动物和患有溃疡的动物中，暴露于不同浓度（0%、2%或4%）的香烟烟雾后，测定胃黏膜鸟氨酸脱羧酶活性、黏液分泌层厚度和溃疡大小。还评估了香烟烟雾提取物处理的MKN-28细胞中黏液的合成、鸟氨酸脱羧酶活性和mRNA表达。
暴露于香烟烟雾显著降低了有或无溃疡动物的黏液分泌层厚度和胃黏膜鸟氨酸脱羧酶活性。亚精胺不仅逆转了完整动物和患溃疡动物中黏液合成的抑制，还逆转了溃疡愈合的延迟。香烟烟雾提取物显著降低了MKN-28细胞中的黏液合成和鸟氨酸脱羧酶活性，但未降低其mRNA表达。亚精胺恢复了黏液合成的减少。
香烟烟雾及其提取物分别在体内和体外抑制黏液合成。胃黏膜中鸟氨酸脱羧酶活性的降低与这种作用密切相关。
