Figure 1

Cellular responses. Total BAL PMNs (A), lung homogenate MPO activity (B) and total BAL alveolar macrophages (AM) (C) in mice 24 h following the intratracheal administration of LPS (150 ng/gm) or PBS. Some of the mice received doxycycline, 2 mg/kg in the drinking water starting 72 h prior to the administration of LPS. The BAL PMN were increased only in the LPS-treated mice without doxy, whereas lung MPO activity was increased in LPS-treated mice with and without doxy. This suggests that neutrophils accumulated in the lungs, but did not enter the alveolar spaces. n: PBS = 3; Doxy = 5, LPS = 5, LPS + Doxy = 6.