Effects of rolipram on BAL inflammatory cells and mucous cell metaplasia in airway epithelium. Rats were gavaged with vehicle or 10 mg/kg body weight rolipram 2 h prior to exposure to LPS aerosol (15 μg deposited pulmonary dose). BAL was performed at 8, 24 and 72 h following LPS inhalation and the numbers of (A) total cells, (B) neutrophils, and (C) macrophages were quantified. For the harvest at 8 and 24 h, the whole lung was lavaged two times each using 5 ml of saline. For the harvest at 72 h, the right lungs were lavaged two times each with 3 ml of saline and the left lung was inflated with 10% zinc formalin under a constant pressure for 3 h. (D) mucous cell number per mm BL and (E) the amount of intraepithelial stored mucosubstances expressed as Vs were quantified. Values are group means ± SE; (n = 6 rats per group). * = Significantly different, P < 0.05.