银杏叶提取物、银杏黄酮和银杏内酯B对小鼠脑缺血／再灌注损伤的保护作用

目的比较银杏叶提取物及其主要成分银杏黄酮和银杏内酯B对小鼠脑缺血／再灌注损伤的保护作用。方法建立小鼠脑缺血／再灌注损伤模型，观察比较银杏叶提取物、银杏黄酮、银杏内酯B对小鼠存活时间、脑含水量及脑皮质组织中Na^＋-K^＋-ATP酶活性、丙二醛（MDA）含量、超氧化物歧化酶（SOD）活性的影响。结果银杏叶提取物300mg·kg。能显著延长小鼠的存活时间，降低小鼠脑含水量，提高脑皮质组织中Na^＋-K^＋-ATP酶活性，抑制MDA含量增加和SOD活性降低（P〈0．01）。银杏内酯B和银杏黄酮亦有相似的作用，其中银杏内酯B对皮质Na^＋-K^＋-ATP酶活性的影响显著（P〈0．01），而银杏黄酮能显著降低皮质中MDA的含量（P〈0．01）。结论银杏叶提取物、银杏内酯和银杏黄酮对小鼠全脑缺血／再灌注损伤均具有保护作用，银杏内酯B较银杏黄酮有较好的抑制脑水肿、提高Na^＋-K^＋-ATP酶活性的作用，而银杏黄酮抗氧化作用较优于银杏内酯B。

The protective effects of Ginkgo biloba extract, total Ginkgo flavonoids and ginkgolide B against global cerebral ischemia/reperfusion injury in mice

Objective To compare the protective effects of Ginkgo Biloba extract （GbE）, Ginkgo flavonoids （GF） and ginkgolide B （GB） on global isebemia/reperfusion injury in mice. Methods The mice global isehemia/reperfusion injury model was established. Mice were pretreated with GbE, GF and GB separately. The survival time, brain water content, activity of Na ^＋ - K^＋ - ATPase, MDA content, activity of SOD in mice cerebral cortex were detected after 20 min ischemia and 24 h reperfusion. Results 300 mg· kg^-1 of GbE could obviously extend the mice survival time, reduce the brain water content, enhance Na^ ＋ -K ^＋ -ATPase activity, suppress the MDA content and increase the SOD activity in mice cerebral cortex （P 〈0.01 ）. GB and GF had the similar tendency, in which GB significant enhanced Na^＋ -K^＋ - ATPase activity in the cortex and decreased brain water content （P 〈 0. 01 ）. GF reduced the content of MDA in the cortex significantly （P 〈 0.01 ）. Conclusion GbE, GF and GB can protect the mice against global cerebral isehemia/ reperfusion injury. Compared with GF, GB has a better effect against cerebral edema and enhance the Na ^＋ -K^＋ -AT- Pase activity. However, GF has the better antioxidant effect than GB.