Localized pulmonary neutrophil influx induced by lung lavage in sheep

The kinetics and distribution of neutrophil (PMN) influx into lung air spaces subsequent to bronchoalveolar lavage (BAL) were studied in adult sheep. The concentration of PMNs in BAL fluid peaked at 6 h and remained elevated for 48 h after the initial lavage. The response was observed primarily in the lung segment originally lavaged although minor changes were seen in BAL from immediately adjacent regions. No response was observed in the contralateral lung. Except for a transient decrease in pulmonary alveolar macrophages and monocytes at 6 h, changes in mononuclear cell populations (pulmonary alveolar macrophages, monocytes and lymphocytes) were minimal.