论文部分内容阅读
目的:研究外源性脑源性神经因子(BDNF)对条件敲除缝隙链接蛋白26(Cx26)小鼠耳蜗形态和功能的影响。方法:选取条件敲除的Cx26小鼠为动物模型,在出生后2d(P0-P2)通过中阶注射给予外源性BDNF。分别观察BDNF在耳蜗中的表达情况及其对神经纤维生长的促进作用,注射后60d,BDNF对corti器及螺旋神经节细胞的保护作用,并检测注射后动物听力的改变情况。结果:(1)外源性BDNF可在实验动物体内良好表达;(2)外源性BDNF对动物耳蜗神经纤维生长有良好的促进作用;(3)外源性BDNF可有效保护corti器的形态;计数耳蜗各回螺旋神经节细胞数,以未注射耳顶回的密度值作为标准单位,注射耳中回和底回的密度值分别为0.81±0.02、0.65±0.02,与未注射耳相比,均差异有统计学意义(均P<0.05);(4)通过计算注射耳与未注射耳各频率ABR阈值,显示两者差异无统计学意义。结论:早期给予外源性BDNF可有效保护条件敲除Cx26小鼠耳蜗的corti器及螺旋神经节细胞的形态,但对于听功能则无保护作用。
AIM: To investigate the effects of exogenous brain-derived neurotrophic factor (BDNF) on the morphology and function of the cochlea in Cx26 mice. Methods: Cx26 mice were selected as animal models, and exogenous BDNF was administered by medium-order injection 2 days after birth (P0-P2). The expression of BDNF in cochlea and the promotion of nerve fiber growth were observed respectively. The protective effects of BDNF on corti and spiral ganglion cells 60 days after injection were observed, and the changes of animal’s hearing after injection were detected. Results: (1) Exogenous BDNF was well expressed in experimental animals; (2) Exogenous BDNF promoted the growth of cochlear nerve fibers; (3) Exogenous BDNF could effectively protect the morphology of corti The numbers of spiral ganglion cells in each cochlea were counted, and the density of non-injected apex was counted as the standard unit. The density of the back and the bottom of the ear was 0.81 ± 0.02,0.65 ± 0.02, respectively. Compared with the uninjected ears, (P <0.05). (4) By calculating the ABR threshold of each frequency of injected and uninjected ears, there was no significant difference between the two groups. CONCLUSION: Exogenous BDNF can effectively protect the corti and spiral ganglion cells in Cx26 mice cochlea conditionally, but have no protective effect on hearing function.