CLDN5 and acute respiratory distress syndrome: Qualitative and quantitative analysis of Claudin-5, ZO-1, and VE cadherin protein showed that the expression of Claudin-5, ZO-1, and VE cadherin protein decreased in different degrees when oleic acid-induced ALI; KGF- 2 After pretreatment, the expression of Claudin-5, ZO-1, and VE cadherin protein recovered to different extents.