BDNF基因对噪音引起的听神经元损伤的保护作用

THE INFLUENCE OF BRAIN DERIVED NEUROTROPHIC FACTOR ON THE SURVIVAL OF SPIRAL GANGLION NEURONS AFTER NOISE TRAUMA

目的 有效地利用BDNF基因对噪音引起的听神经元损伤进行治疗。 方法 利用噪音制备豚鼠耳聋模型 ,在噪音损伤 7d后 ,通过圆窗膜注入 10 8重组腺病毒。注入Ad BDNF病毒的为实验组 ,Ad lacZ为对照组。 4周后 ,取耳蜗组织固定切片 ,进行BDNF抗体免疫细胞化学染色和HE染色。 结果 经BDNF抗体免疫细胞化学染色可见 ,注入Ad BDNF病毒的实验组中 ,在内耳多种细胞中可见明显的BDNF蛋白表达。同时 ,HE染色显示 ,注射Ad BDNF的实验组中螺旋神经节细胞的数目明显多于对照组 ,细胞的状态也与正常动物相近 ,细胞质丰富且细胞核边界清晰。注射Ad LacZ组的豚鼠耳蜗螺旋神经节细胞明显退变。 结论 腺病毒介导的BDNF基因可长期表达于内耳中 。

Objective To use BDNF gene to prevent auditory nerve degeneration after noise\|induced injury. Methods Deafness guinea pig model was made by using intense noise exposure, which destroyed the entire organ of Corti in the middle part of the cochlea. Seven days after noise exposure, the animals were anesthetized, 10\+8 recombinant adenoviral particles were injected into the scala tympani through the round window membrane. Animals inoculated with Ad\|BDNF were designated as the experimental group, animals inoculated with Ad\|lacZ vector served as the control group. Four weeks after the inoculation of the virus, the animals were deeply anesthetized and decapitated. The cochlear were fixed and serial sections were cut. The sections were stained with HE solution and BDNF antibody, respectively. Results BDNF immunohistochemistry results showed that the immunostain reaction product was observed in the experimental group.HE histochemical staining results showed that the density of spiral ganglion neurons in the Ad\|BDNF injected group was significantly higher than that of the Ad\|lacZ injected group. The spiral ganglion neuron appeared healthy with abundant cytoplasm and clear nuclei and nucleoli. In the Ad\|LacZ injected group, the neural degeneration was most severe.Conclusion Our results demonstrate that adenovirus\|mediated overexpression of BDNF may be developed as a pharmacological treatment to prevent secondary auditory nerve degeneration following organ of Corti damage.