银杏叶提取物与去铁胺合用防治顺铂耳毒性实验研究

目的银杏叶提取物-金纳多(extract of Ginkgo Biloba leaves injection，EGb)和铁螯合剂-去铁胺(Deferoxamine，DFO)联合应用对抗顺铂(Cisplatin，CDDP)耳毒性的作用。方法将豚鼠随机分为CDDP组、EGb组、DFO组、EGb+DFO组及对照组，测定听性脑千反应(auditory brain—stem response，ABR)、血清超氧化物歧化酶(superoxide dismutase，SOD)活性和丙二醛(MDA)含量及应用光镜、及扫描电镜技术，观察用药前后各指标的变化。结果CDDP组动物ABR阈值较其他各组明显升高(P<0．01)，其余各组间差异不显著(P>0．05)。血清SOD活性和MDA含量检测表明，CDDP组血清SOD活性较对照组明显降低(P<0．01)，MDA含量显著升高(P<0．01)，其他组较对照组则差异无显著性(P>0．05)。耳蜗扫描电镜显示EGb+DFO组和DFO组比CDDP组毛细胞受损程度明显为轻，EGb组较CDDP组毛细胞受损程度略微减轻。结论DFO与EGb合用，可有效减轻CDDP的耳毒性作用，其效果优于单独应用EGb，与单独应用DFO效果相当，二者合用还可能减轻顺铂的骨髓抑制副作用。结果提示铁离子参与的自由基反应可能是顺铂耳毒性机制之一。

Effect of Combination of Ginkgo Leaf Extract and Deferoxamine in Preventing and Treating Ototoxicity of Cisplatin

Objective To observe the effect of combined use of Jinnaduo (an injection made by extract of Ginkgo leaf, EGb) and Deferoxamine (DFO, a chelating agent) in antagonizing the ototoxicity of cisplatin (CDDP). Methods Guinea pigs were randomly divided into the CDDP group, the EGb group, the DFO group, the combined treated group (EGb DFO) and the control group. Changes of auditory brain stem response (ABR), serum superoxide dismutase (SOD) activity and malondialdehyde (MDA) content, as well as light and scanning electronic microscopic (SEM) figures were observed before and after treatment. Results The threshold of ABR was significantly higher in the CDDP group than that in the other groups (P<0.01), but was insignificantly different among the latter groups (P>0.05). Serum SOD activity was lower and MDA content was higher in the CDDP group than those in the control group (P<0.01), but in comparison of the two parameters between control and other groups, the difference was insignificant (P>0.05). SEM examination on cochlea showed that the damage of hair cells was milder in the DFO group and the combined treated group than that in the CDDP group, which was slightly milder in the EGb group than that in the CDDP group. Conclusion Combined use of EGb and DFO could effectively reduce the ototoxicity of CDDP, its effect is better than using EGb singly, and similar to that of using DFO alone. The combination could also prevent the side effect of CDDP in bone marrow inhibition. The Fe ion participated free radical response could be one of the mechanisms of CDDP in damaging hearing.