Alveolar epithelial fluid transport can be simultaneously upregulated by both KGF and beta -agonist therapy

Cardiovascular Research Institute and Departments of Medicine, Anesthesia, and Physiology, University of California, San Francisco, California 94143-0130 Although keratinocyte growth factor (KGF) protects against experimental acute lung injury, the mechanisms for the protective effect are incompletely understood. Therefore, the time-dependent effects of KGF on alveolar epithelial fluid transport were studied in rats 48-240 h after intratracheal administration of KGF (5 mg/kg). There was a marked proliferative response to KGF, measured both by in vivo bromodeoxyuridine staining and by staining with an antibody to a type II cell antigen. In controls, alveolar liquid clearance (ALC) was 23 ± 3%/h. After KGF pretreatment, ALC was significantly increased to 30 ± 2%/h at 48 h, to 39 ± 2%/h at 72 h, and to 36 ± 3%/h at 120 h compared with controls ( P