Chronic cigarette sidestream smoke exposure increases rat trachea ornithine decarboxylase activity

The effect of chronic cigarette smoke exposure on the activity of rat trachea and lung ornithine decarboxylase (ODC) and s-adenosyl-methionine decarboxylase (AdoMet-DC) was determined. Male rats were exposed once daily for 10 min to mainstream (MS) or different sidestream (SS) dilutions of fresh Kentucky 2R1 cigarette smoke or air (sham) for 4, 8 or 20 weeks. Eight weeks of MS smoke significantly increased lung and trachea ODC activity. All dilutions of SS smoke exposure caused significant increases in trachea ODC activity, but SS smoke did not influence lung ODC activity. The data demonstrate that long term exposure to passive smoke generated from cigarettes can increase rat trachea ODC activity.