Figure 4.

Adult mice exposed to prenatal nicotine have significantly greater numbers of small bronchioles compared with unexposed control animals. C57BL6/J female mice were administered either untreated water or water containing 100 μg/ml nicotine before timed breeding and through gestation. Lungs were obtained from age-matched offspring at 8 weeks of age. Whole lungs were embedded and sectioned in an isotropic, uniform random manner to create unbiased samples for examination. Airway diameter was measured for each visible bronchus and bronchiole. Mice exposed to prenatal nicotine had significantly greater numbers of small bronchioles, with diameters between 60–90 μm (n = 8 per group). Error bars denote SD. *P < 0.05 compared with control.