银杏叶提取物对新生SD 乳鼠心肌细胞缺氧损伤的影响

目的:研究银杏叶提取物对缺氧状态下新生SD乳鼠心肌细胞的影响及其可能机制。方法:新生1天SD乳鼠心肌细胞原代培养并利用氮气培养箱模拟低氧构建乳鼠心肌缺氧体外模型。分为3组处理:对照组,缺氧组,缺氧+药物拮抗组。缺氧时间为12 h,通过免疫组化等检测方法,观察各组心肌细胞的损伤情况及心肌Bcl-2、Bax蛋白表达情况。结果:缺氧可以造成新生SD乳鼠心肌细胞凋亡的发生(hypoxia:75.21%±1.21%,control:1.38%±0.45%,P<0.05,n=20),并导致其表达凋亡抑制因子Bcl-2蛋白水平的显著降低(0.125 fold VS control group,P<0.05),促细胞凋亡因子Bax蛋白水平显著升高(3.011fold VS control group,P<0.05);而银杏叶提取物作用后可明显逆转新生SD乳鼠心肌细胞凋亡的发生(EGb761:23.17%±0.43%,hypoxia:73.13%±1.22%,P<0.05,n=20),并明显逆转Bcl-2(5.716 fold VS hypoxia group,P<0.05)、Bax(0.273fold VS hypoxia group,P<0.05)等蛋白的表达水平。结论:凋亡相关因子Bcl-2和Bax等参与缺氧致心肌损伤过程,导致心肌细胞凋亡,银杏叶提取物能降低心肌Bax表达,提高Bcl-2表达,从而保护心肌细胞,抑制凋亡。

The Effect of Extract of Ginkgo Biloba Leaf on Neonatal SD Rat MyocardialCells during Hypoxic Injury

Objective: To investigate the effect of extract of ginkgo biloba leaf on neonatal SD rat myocardial cells during hypoxic injury and its possible mechanism.Methods: Neonatal 1 d SD rats’ myocardial cells were cultured and the nitrogen incubator was used to mimic hypoxia model in vitro.Primary cultures were divided into three groups: blank group,hypoxia group,hypoxia and medicine inter-ference group.For the hypoxia group and hypoxia plus medicine interference group,cells were cultured in hypoxia incubator for 12 h,then the expression of Bcl-2 and Bax were detected by western blot and the cell apoptosis was detected with in situ TUNEL assay.Results: The apoptosis of neonatal SD rat myocardial cells were detected after 12 h hypoxia(hypoxia: 75.21 %±1.21 %,control: 1.38 %±0.45 %,P<0.05,n=20).Meanwhile,hypoxia also reduced expression of Bcl-2(0.125 fold VS control group,P<0.05) and elevated expression of Bax(3.011fold VS control group,P<0.05).Moreover,the extract of ginkgo biloba leaf could significantly inhibit the apoptosis of neonatal SD rat myocardial cells exposed to hypoxia(EGb761: 23.17 % ± 0.43 %,hypoxia: 73.13 % ± 1.22 %,P<0.05,n=20) and sig-nificantly invert the expression of Bcl-2(5.716 fold VS hypoxia group,P<0.05) and Bax(0.273fold VS hypoxia group,P<0.05).Conclusion: Apoptosis-related factors such as Bcl-2 and Bax may play an important role in the process of hypoxia-induced myocardial cells injury,which may lead to myocardial cells apoptosis.The extract of ginkgo biloba leaf could reduce the expression of Bax and elevate the ex-pression of Bcl-2,and accordingly protect myocardial cells from hypoxia induced apoptosis.