银杏叶提取物对犬低温体外循环肺损伤的保护作用

目的 观察银杏叶提取物对犬低温体外循环时肺损伤的保护作用。方法 将14只健康杂种犬随机分为对照组和银杏组，每组7只。银杏组在犬麻醉后开胸之前给予银杏叶提取物金纳多8mg/kg静脉滴注，对照组以等量生理盐水同速度静脉滴注。体外循环60min，心脏复跳并循环120min后采集肺组织检测肺组织湿/干重比及通透性，用生化法检测肺组织丙二醛(MDA)含量、髓过氧化物酶（MPO)活力、总超氧化物歧化酶(T-SOD)活力，用ELISA法检测肺组织白介素1-β(IL-1β)、白介素-8(IL-8)、肿瘤坏死因子-α(TNF-α)、血小板活化因子(PAF)水平。结果 与对照组比较，银杏组肺组织湿/干重比减少，通透性降低（P<0.05)；MDA含量减少、MPO 活力降低，T-SOD活力升高（P<0.05)；IL-1β、IL-8、PAF水平明显降低（P<0.05)。结论 银杏叶提取物对犬低温体外循环肺损伤有较好的保护作用，其机制可能与其减轻体外循环时肺组织缺血再灌注损伤和全身炎症反应相关。

Protective Effects of Ginkgo biloba Extract on the Lung Injury of Dogs Undergoing Hypothermic Cardiopulmonary Bypass

Objective To study the protective effects of Ginkgo biloba extract(EGb) on the lung injury of dogs undergoing hypothermic cardiopulmonary bypass(CPB).Methods Fourteen healthy hybrid dogs were randomly divided into the control group and the EGb group,7 in each group.EGb(8 mg/kg) was intravenously dripped to dogs in the EGb group before thoracotomy after anesthesia,while equal volume of normal saline was intravenously dripped to those in the control group.The lung tissue was collected after 60-min CPB and 120-min recovery of heart beat.The lung tissues were collected to detect the wet weight-dry weight ratio and the permeability.The contents of malondialdehyde(MDA),the activities of myeloperoxidase(MPO) and total superoxide dismutase(T-SOD) in the lung tissues were detected by biochemical assay.The levels of IL-1β,IL-8,tumor necrosis factor α(TNF-α),platelet activating factor(PAF) in the lung tissue were detected by enzyme linked immunosorbent assay(ELISA).Results Compared with the control group,the wet weight-dry weight ratio was reduced and the permeability of the lung tissue decreased(P<0.05),the MDA content was reduced,the activity of MPO decreased,and the activity of T-SOD increased(P<0.05),and the levels of IL-1β,IL-8,and PAF obviously decreased(P<0.05).Conclusions EGb showed better protective effects on the lung injury of dogs undergoing hypothermic CPB.Its possible mechanisms might be associated with alleviating ischemia-reperfusion injury of in vitro circulation and systemic inflammatory response.