Repeated allergen inhalations induce DNA synthesis in airway smooth muscle and epithelial cells in vivo

tin. Repeated allergen inhalations induce DNA synthesis in airway smooth muscle and epithelial cells in vivo. Am. J. Physiol. 274 (Lung Cell. Mol. Physiol. 18): L417–L424, 1998.— Airway smooth muscle (ASM) mass appears to be increased in the bronchi of patients with chronic severe asthma. Although the precise mechanisms that induce these changes are un-known, increases in ASM mass are caused, in part, by ASM cell proliferation. After allergen challenge in rats, it has been possible to demonstrate an increase in ASM mass by morpho-metric techniques. To examine whether hyperplasia is in-volved in ASM cell growth in vivo, we investigated whether repeated allergen challenges in sensitized Brown Norway rats stimulated DNA synthesis in airway epithelial and ASM cells. Animals that were actively sensitized to ovalbumin (OA) received either three aerosolized OA or saline challenge