银杏叶提取物改善兔心肌缺血/再灌注损伤及微循环障碍的作用

Ginkgo Biloba Extract Combating Microcirculatory Dysfunction and Injury Induced by Ischemia/Reperfusion in Rabbits

在兔心脏缺血／再灌注（I／R）损伤模型上．对照观察了银杏叶提取物（GBE）的作用。发现：与I／R组相比，I／R＋GBE组血浆中一氧化氛（NO）、超氧化物歧化酶（SOD）、6－酿－前列腺素F1α（6－K－PGF1α）浓度明显升高，而血栓素B2（TXB2）、丙二醛（MDA）明显下降。GBE组血管增多，肿胀内皮细胞减少，线粒体件胀减轻。痉挛球结膜微血管扩张，扩散距离缩小。结果表明：GBE具有明显的扩张微血管作用，尤其对微动脉更明显。这可能由于它能够刺激血管内皮细胞释放NO及PGI2并减少其失活。GBE可被认为是心血管NO释放的刺激剂，用于防治心肌I／R损伤是有效的。

We observed protcctive effects of Ginkgo biloba extract(GBE)on experimental rabbits in theischemia/reperfusion model. The concentration of plasma nitric oxide (NO),superoxide dismutase (SOD), and6-k-PGF1α increased,but that of TXB,,ma1ondialdehyde (MDA )decreased markedly in comparison with that ofI/R group. The results demonstrated that myocardial morphology was normal in GBE group. Ultrastructureshowed that the number of opening capillary increased, but swollen endothelial cell and mitochondria decreased. The velocity of blood stream in bulbar conjunctiva microvessels turned fast markedly and spasm microvessles dilated. These results indicated that GBE can dilate microvessels. Under most circumstances,the effects were more prominent in arteriole than in venule. The possible reason was assumed to trigger endothelialcell to release NO. GBE could be regarded as a potent stimulus for cardiovascular tissue to release NO. Itsbenfficial effect on myocardial ischemia/reperfusion injury should be assured.