方法：建立兔青光眼缺血再灌注模型，72只新西兰大白兔随机分为神经生长因子组(A组)、银杏叶提取物组(B组)和联合用药组(C组)。分别在持续给药1、7、14d，光镜下观察视网膜各层组织形态学改变，测定视网膜组织中超氧化物歧化酶(superoxide dismutase，SOD)、一氧化氮(nitric oxide，NO)、丙二醛(malondialdehyde，MDA)浓度变化。

结果：在持续给药1、7、14d，银杏叶提取物组、神经生长因子组的MDA含量和NO含量均高于联合用药组(P<0.05)； 各时间点，银杏叶提取物组、神经生长子组的SOD含量均低于联合用药组(P<0.05)。HE染色视网膜神经节细胞(retinal ganglion cells，RGCs)计数结果显示，联合用药组RGCs的丢失较其他组明显减少，各时间点银杏叶提取物组、神经生长因子组的RGCs计数均低于联合用药组(P<0.05)。

结论：神经生长因子联合银杏叶提取物对RIR损伤具有更好更持久的保护作用，机制可能与其降低自由基的大量产生，以及其增加视网膜组织中SOD含量和活性有关。

METHODS: Establishment of rabbit glaucoma ischemia reperfusion model. Twenty-four New Zealand white rabbits were randomly divided into three groups: nerve growth factor group, Ginkgo biloba extract group and combination group. Respectively, in the continuous administration of 1, 7, 14d. We observed the morphological changes of the tissues of the retina. The levels of superoxide dismutase(SOD), nitric oxide(NO)and malondialdehyde(MDA)in retinal tissue were measured.

RESULTS: Respectively, first, in the continuous administration of 1, 7, 14d, the contents of MDA and NO in Ginkgo biloba extract group and nerve growth group were higher than that in combination group(P<0.05). Secondly, the SOD content of Ginkgo biloba extract group and nerve growth group were lower than that of combination group at each time point(P<0.05). At each time point, the number of HE staining of retinal ganglion cells(RGCs)showed that the loss of RGCs in the combination group was significantly lower than that in the other groups, and the ganglion cell count showed that the Ginkgo biloba extract group and the neuronal growth group were lower(P<0.05).

CONCLUSION: Nerve growth factor combined with Ginkgo biloba extract has better protective effect on retinal ischemia-reperfusion injury. The mechanism may be related to the decrease of free radicals and increase the activity of SOD in retinal tissue.