title: [Resisting injury and protective effect of fibronectin on bronchial epithelial cells].
abstract: OBJECTIVE
  To test the hypothesis that activation of integrin molecules play a role on protecting bronchial epithelial cells (BEC) from oxidant injury. Based on a cell-injury model made by ozone (1.5 x 10(-6)) exposure, the present study investigated the protective effect of fibronectin (Fn), a kind of ligand of integrin, and it's specific sequence Arg-Gly-Asp (RGD peptide) which is a recognizable domain for integrin on BEC. 3H release, LDH and MDA were measured as indexes for damage.
  
  
  RESULTS
  (1) Ozone exposure induced a significant increase of 3H release and LDH release from BEC and elevation of MDA. (2) Pretreatment with Fn or RGD before ozone exposure markedly attenuated the release of 3H, LDH and MDA, and the effects of Fn were reversed by W7, a calmodulin inhibitor. (3) Either Fn or RGD up-regulated activity of catalase in BEC and promoted GSH synthesis in BEC.
  
  
  CONCLUSIONS
  These suggests that the binding of integrin with Fn improve the antioxidant ability of BEC and lighten the damage induced by oxidant attack. The protective mechanism of Fn-integrin binding may be related with calmodulin.
authors.affiliation: Department of Physiology, Xiangya Medical School, Central-South University, Changsha 410078, China.
authors.forename: C Q
authors.initials: CQ
authors.lastname: Zhang
authors.forename: X Q
authors.initials: XQ
authors.lastname: Qin
authors.forename: C X
authors.initials: CX
authors.lastname: Guan
authors.forename: Y
authors.initials: Y
authors.lastname: Xiang
authors.forename: X H
authors.initials: XH
authors.lastname: Sun
mesh_terms: D000818:Animals; D001980:Bronchi / Q000166:cytology; D002478:Cells, Cultured; D004847:Epithelial Cells / Q000187:drug effects*; D005353:Fibronectins / Q000494:pharmacology*; D009842:Oligopeptides / Q000494:pharmacology*; D010126:Ozone / Q000009:adverse effects*; D011817:Rabbits
chemical_list: D005353:Fibronectins; D009842:Oligopeptides; D010126:Ozone; C047981:arginyl-glycyl-aspartic acid