Altered plasminogen activator inhibitor-1 mRNA expression in experimental lung injury and the effect of inhaled nitric oxide / 中国小儿急救医学

ABSTRACT

Objective To observe the changes of plasminogen activator inhibitor-1(PAI-1)mRNA expression in experimental lung iniury and to evaluate the effect of inhaled nitric oxide(NO)on PAI-1 mRNA expression.Methods In this study,acute lung injury rat model was established by lipopolysaccharide(LPS)-induced endotoxemia followed by a second LPS attack via intratracheal injection.Eighty-nine SD male rats aged 4～5 week were randomly assigned to three groupssaline control(C-A)group,LPS-A group attacked by LPS,LPS-NO group treated by nitric oxide.Realtime PCR was used to study the expression of PAI-1 mRNA in the lung.Histopathological lung injury score was evaluated.Results In LPS group,the histopathological lung injury score values were significantly higher than that of C-A group at 2 h[(3.10±0.38)vs(1.12±0.84)](P＜0.05)and the score values after 2 h were higher than that of LPS group at 2 h(P＜0.05).PAI-1 mRNA in lung increased gradually in LPS groups at 2 h,4 h,8 h,16 h,24 h(P＜0.05)and decreased at 48 h(P＞0.05).The PAI-1 mRNA decreased in LPS-NO groups at 4h(P＜0.05).Conclusion The study above demonstrates that PAI-1 mRNA expression is early elevated in rats with endotoxin-induced acute lung injury.Decreased PAI-1 mRNA expression is associated with the efficacy of inhaled nitric oxide.