title: Attenuation of endotoxin-induced acute lung injury by the Rho-associated kinase inhibitor, Y-27632.
abstract: A small GTPase, Rho, plays key roles in cell adhesion, motility, and contraction after stimulation. Among Rho effectors isolated, the family of Rho-associated coiled-coil-forming protein kinases (ROCK) is implicated in Rho-mediated cell adhesion and smooth muscle contraction. The effect of a specific inhibitor of ROCK, Y-27632, was evaluated in a murine model of acute lung injury induced by intravenous injection of Escherichia coli endotoxin (lipopolysaccharide [LPS]). Lung edema was evaluated by measuring extravascular leakage of radio-labeled serum albumin, and neutrophil emigration into the lung parenchyma by morphometric observation and measuring myeloperoxidase activity. Pretreatment with Y-27632 attenuated both lung edema and neutrophil emigration after LPS. We also measured albumin transfer through cultured endothelial cell monolayers on a porous filter. Tumor necrosis factor-alpha significantly increased albumin transfer, which was attenuated by pretreatment with Y-27632. Fluorescence microscopy revealed that morphologic changes in endothelial cells induced by tumor necrosis factor-alpha were inhibited by Y-27632. In contrast, the increased fraction of neutrophils with polymerized actin after formyl-methionyl-leucyl-phenylalanine was not altered by Y-27632. These data suggest that ROCK may play an important role in the pathogenesis of LPS-induced lung injury and that ROCK inhibition could attenuate cytoskeletal rearrangement of endothelial cells, leading to decreased neutrophil emigration into the lung parenchyma.
authors.affiliation: Department of Medicine, Keio University School of Medicine, 35 Shinanomachi, Tokyo 160-8582, Japan.
authors.forename: Sadatomo
authors.initials: S
authors.lastname: Tasaka
authors.forename: Hidefumi
authors.initials: H
authors.lastname: Koh
authors.forename: Wakako
authors.initials: W
authors.lastname: Yamada
authors.forename: Mie
authors.initials: M
authors.lastname: Shimizu
authors.forename: Yuko
authors.initials: Y
authors.lastname: Ogawa
authors.forename: Naoki
authors.initials: N
authors.lastname: Hasegawa
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Yamaguchi
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Ishii
authors.forename: Sarah E
authors.initials: SE
authors.lastname: Richer
authors.forename: Claire M
authors.initials: CM
authors.lastname: Doerschuk
authors.forename: Akitoshi
authors.initials: A
authors.lastname: Ishizaka
mesh_terms: D000577:Amides / Q000494:pharmacology*; D000818:Animals; D002465:Cell Movement / Q000276:immunology; D004727:Endothelium / Q000378:metabolism / Q000473:pathology; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D047908:Intracellular Signaling Peptides and Proteins; D007958:Leukocyte Count; D008070:Lipopolysaccharides; D051379:Mice; D008810:Mice, Inbred C57BL; D009504:Neutrophils / Q000166:cytology; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors*; D011650:Pulmonary Alveoli / Q000201:enzymology / Q000276:immunology / Q000473:pathology; D011654:Pulmonary Edema / Q000139:chemically induced / Q000188:drug therapy / Q000276:immunology; D011725:Pyridines / Q000494:pharmacology*; D012128:Respiratory Distress Syndrome / Q000139:chemically induced / Q000188:drug therapy* / Q000276:immunology; D012709:Serum Albumin / Q000378:metabolism; D054460:rho-Associated Kinases
chemical_list: D000577:Amides; D004791:Enzyme Inhibitors; D047908:Intracellular Signaling Peptides and Proteins; D008070:Lipopolysaccharides; D011725:Pyridines; D012709:Serum Albumin; C108830:Y 27632; D017346:Protein Serine-Threonine Kinases; D054460:rho-Associated Kinases