GluR4在单侧聋大鼠耳蜗核不同发育时间的表达

GluR4 Expression in Cochlear Nucleus of Rats with Single-side Deafness at Different Developmental Stages

目的观察单侧耳蜗毁损后1、2、3、4周谷氨酸受体4(glutmate receptor 4,GluR4)在大鼠耳蜗核的表达变化,为探讨单侧聋听觉中枢重组的分子机制提供参考。方法新生SD大鼠饲养至出生后12 d(P12),随机分为实验组(左侧耳蜗毁损32只)、伪手术组(进行伪操作32只)及对照组24只,术后1、2、3、4周取三组大鼠双侧耳蜗核,切片后采用免疫组化方法观察耳蜗核GluR4的表达变化。结果伪手术组及对照组大鼠术后1、2、3、4周,双侧耳蜗核之间比较GluR4表达无统计学差异(P>0.05);伪手术组及对照组双侧耳蜗核GluR4的表达在不同发育时间比较,术后1周与2周相比,2周与3周相比差异均有显著统计学意义(P<0.01)。实验组大鼠耳蜗核两侧之间对比,术后1、2、3周双侧表达差异均有统计学意义(P<0.05);在不同发育时间对比,实验组术侧耳蜗核中GluR4的表达在术后2周与3周相比表达差异有显著统计学意义(P<0.01),而术后1周与2周、3周与4周相比无统计学差异(P>0.05)。实验组健侧术后2周与3周相比表达差异有统计学意义(P<0.05),术后3周与4周相比表达差异有统计学意义(P<0.05)。结论单侧聋大鼠双侧耳蜗核GluR4的表达在发育中存在不对称改变。

Objective To observe the expression of glutamate receptor 4(GluR4)in the cochlear nucleus of rats 1,2,3 and 4 weeks after unilateral cochlear lesion,so as to provide reference for exploring the molecular mechanism of central auditory system reorganization in single-side deafness.Methods Newborn SD rats were fed to P12,and half of the newborn rats in each cage were randomly selected for unilateral cochlear destruction surgery.One week,two weeks,three weeks and four weeks after surgery,bilateral cochlear nuclei of the experimental group and the corresponding time control group were retreived,and the expression changes of GluR4 in the cochlear nuclei were observed by immunohistochemical method.Results GluR4 was expressed in different degrees in the cochlear nucleus of each group.The positive sediment was mainly located in the cytoplasm and membrane,and was also expressed in the perinuclear cytoplasm.There was no significant difference in the expression of GluR4 between the left and right cochlear nucleus of rats in the pseudo-operation group and the control group at 1,2,3 and 4 weeks after operation(P>0.05).Comparison at different development time,the expression of GluR4 in bilateral cochlear nuclei in the pseudo-operation group and the control group was significantly different from that in the first and second weeks after operation,and the second and third weeks after operation(P<0.01).There were significant differences in the expression between left and right side in the experimental group at 1 week,2 weeks and 3 weeks after operation(P<0.05).Comparison at different development time,the expression of GluR4 in the cochlear nucleus of the operative side of the experimental group was significantly different between the two and three weeks after operation(P<0.01),but there was no statistical difference between the two and three weeks after operation(P>0.05).The expression difference of the contralateral side in the experimental group was statistically significant at 2 and 3 weeks after operation(P<0.05),and the expression difference was statistically significant at 3 and 4 weeks after operation(P<0.05).Conclusion There are asymmetric changes in GluR4 in bilateral cochlear nuclei of unilateral deafness rats during development.