The effect of esomeprazole on a lung fibroblast and b alveolar epithelial cell proliferation. Cells were synchronized and then serum-stimulated to induce proliferation in the presence of vehicle or esomeprazole (5–50 µM). Incorporation of BrdU into newly synthesized DNA was quantified spectrophotometrically. Data is Mean ± SEM from duplicate experiments. *p < 0.05 compared to vehicle. BrdU Bromodeoxyuridine.