中文摘要：

目的：利用羟基磷灰石纳米颗粒（hydroxyapatite nanoparticle,HAT）携带构建的神经营养因子-3（neurotrophic factor-3,NT-3）-绿色荧光蛋白基因（enhancement type Green fluorescent protein C2,pEGFPC2）,通过耳蜗灌注方法转染兴奋毒性损伤后的豚鼠耳蜗螺旋神经节细胞（spinal ganglion cells,SGCs）,观察pEGFPC2-NT3的表达及其对耳蜗螺旋神经节细胞的保护作用。方法：构建携带绿色荧光蛋白报告基因的重组质粒pEGFPC2-NT3。通过耳蜗灌注海人酸（kainic acid,KA）建立豚鼠耳蜗兴奋性损伤模型,在给KA1周后利用HAT携带重组质粒进行耳蜗灌注以转染耳蜗螺旋神经节细胞,免疫组化法观察转染后1周NT-3的表达及4周后电镜下螺旋神经节细胞形态学变化,同时观察对听觉脑干诱发电位（auditory brain-stem response,ABR）的影响。结果：成功构建豚鼠耳蜗兴奋损伤模型。灌注重组质粒后1周免疫组化法观察到螺旋神经节细胞胞浆内NT-3蛋白表达。4周后电镜下螺旋神经节细胞形态学损害减轻,ABR检测听功能较兴奋毒性损害后有恢复。结论：在豚鼠耳蜗灌注KA造成耳蜗兴奋性损伤后第7天,经耳蜗鼓阶转染羟基磷灰石纳米颗粒介导的NT-3基因仍可减轻KA对耳蜗螺旋神经节细胞的兴奋性毒性损伤。

英文摘要：

Objective To transfect the recombinant plasmid enhancement type green fluorescent protein C2- neurotrophic factor-3 （ pEGFPC2-NT3 ） into the spinal ganglion ceils （ SGCs ） of guinea pigs＇ cochlea injured by the excitotoxicity of hydroxyapatite anoparticle （ HAT ） , to inject the recombinant plasmid pEGFPC2-NT3 into the spiguinea pigs＇ cochlea, and to observe the expression of pEGFPC2-NT3 and the protective effect of pEGFPC2-NT3 on SGCs of the cochlea in guinea pigs. Methods The recombinant plasmid pEGFPC2-NT3 with gene-green fluorescent protein was established. Kanic acid （KA） was injected into guinea pigs＇ cochleae and the excitotoxicity model was established. After a week the recombinant treated with HAT. The following week the plasmid was transferred into SGCs of guinea pigs＇ cochlea expression of NT-3 was examined by the immunohistochemical method, and the morphology of SGNs was observed under the electronic microscope after 4 weeks, in the mean time the changes of auditory brain-stem response （ABR） were examined. Results The excitotoxicity models were established successfully. NT-3 expression in the intracytoplasm of SGNs was observed by the immunohistochemical method 1 week after the injection, the morphologic damages of SGNs lessened under the electronic microscope after 4 weeks. ABR was partly restored, compared with ABR after the injury of the excitotoxicity. Conclusion On the 7th day, NT3 gene transferred by HAT through the scala tympani can lessen the excitotoxicity of SGCs after KA was injected into the guinea pigs＇cochlea.