ABSTRACT
Objective To investigate the effects of Ginkgo biloba extract (Egb) on the levels of matrix metalloproteinase2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) in canine lung tissues during cardiopulmonary bypass (CPB) .Methods Fourteen health canines weighing 14-20 kg were randomly divided into 2 groups (n = 7 each): control group and Egb group. EGb 8 mg/kg in 100 ml normal saline was infused via central vein before opening the thoracic cavity in Egb group, while equal volume of normal saline was used instead of Egb in control group. Blood samples were taken from internal jugular vein at 120 min after aortic unclamping,broncho-alveolar larage fluid was collected and lung permeability index was calculated. Then the animals were killed and the lungs removed for determination of W/D lung weight ratio and contents of MMP-2 and MMP-9.Results Egb significantly decreased lung permeability index, W/D lung weight ratio and contents of MMP-2 and MMP-9 (P ＜ 0.05 or 0.01). Conclusion Egb can attenuate CPB-induced lung injury though decreasing the activities of MMP-2 and MMP-9 in canine lung tissues.