Effect of in vivo ozone exposure on in vitro pulmonary alveolar macrophage mobility.

The effect of in vivo O3 exposure on the mobility of pulmonary alveolar macrophages (PAM) in vitro was investigated. Eight randomly selected rats were exposed for 4 h. Four rats were exposed to a clean air (sham) atmosphere, and four to an atmosphere containing 1ppm O3. PAM were obtained by lung lavage and placed on gold-colloid coated coverslips. The area cleared of gold particles by migrating PAM after 24, 48, and 72 h was used as an indicator of cell mobility. The number of PAM recoverable by lavage was similar for both groups (2 x 10(5)), but the percentage of macrophages that made tracks was significantly smaller with 95% certainty in the O3 group. For sham-exposed and O3-exposed groups, the area cleared by PAM increased as the length of incubation increased, with the area cleared by the sham-exposed group being about 50% greater during each time period. When the two groups were compared statistically at each time point, the probability that they differed was, in each case, greater than 95%. It was concluded that the in vitro migrational potential of PAM was most likely decreased by in vivo exposure to O3.