Background The extract of Ginkgo bi/oba leaves tablets,ginaton,is widely used in treating ischemic cereebrevascular disease in the clinic.This study aimed to investigate the expression of aquaporin-1 (AQP-1) in rat lung with ischemia/reperfusion injury after pretreatment with ginaton,and whether the pretreatment with ginaton reduces the acute lung injury caused by ischemia/reperfusion injury.Methods Adult Wistar rats were divided into two groups.Some rats were used as donors (n=20),the others as recipients (n=20).Left lungs of donor rats were used for the isolated lung reperfusion model,which perfused only with low potassium dextran (LPD) solution as group A (n=10); the others were pretreated with ginaton before reperfusion as group C (n=10).Right lung of donor rat without any treatment was used as a control group (group B and group D,n=10 for each group).After the model was established,the expression of AQP-1 in the lung tissues was examined by immunohistochemistry,West blotting,and reverse transcriptase-polymerase chain reaction.Results Immunohistochemical examination revealed that AQP-1 was expressed in endothelia.Immunoblotting demonstrated that the relative gray values of AQP-1 protein in groups A and C were 0.65±0.06,0.88±0.11,respectively.The relative gray values of the mRNA expression in groups A and C were 0.30±0.08,0.49±0.11,respectively.The expression of AQP-1 protein and mRNA in group C was significantly higher than in group A (P ＜0.05).Conclusion The pretreatment with ginaton can reduce the acute lung injury caused by ischemia/reperfusion.