硫酸铜及顺铂鼓室内给药对大鼠内耳铜离子转运蛋白表达的影响

Change of CTR1 Expression after Round Window Niche Copper Sulfate and Cisplatin Infusion

目的 了解铜离子转运蛋白1（copper transport protein 1,CTR1）在大鼠内耳的表达情况及硫酸铜和顺铂鼓室给药对CTR1表达的影响。方法 Wistar雄性大鼠24只,随机分为4组,每组6只,Ⅰ组为正常对照组（非处理组）;Ⅱ组为双耳圆窗龛放置顺铂溶液（0.5mg/ml）的明胶海绵;Ⅲ组为双耳圆窗龛放置顺铂溶液（1mg/ml）的明胶海绵;Ⅳ组双耳圆窗龛放置硫酸铜溶液（0.02mg/kg）的明胶海绵。采用免疫组织化学技术,对各组耳蜗冰冻切片行CTR1蛋白的免疫组织化学染色,光学显微镜下观察耳蜗组织中CTR1的表达情况;提取各组耳蜗组织总蛋白,应用Western-blot技术检测各组CTR1蛋白表达水平;提取耳蜗组织的总RNA,应用RT-PCR技术检测各组CTR1mRNA的表达水平。结果 Ⅰ-Ⅳ组大鼠的耳蜗各回Corti器、螺旋神经节、血管纹的细胞质和细胞膜上均有CTR1表达,CTR1的平均光密度值呈降低趋势;各组耳蜗组织均有明显的CTR1表达,Ⅰ-Ⅳ组CTR1蛋白的光密度值分别为0.532±0.031、0.394±0.024、0.234±0.030和0.191±0.015,呈下降趋势,各组间比较差异有统计学意义（P〈0.05）;各组耳蜗组织均有明显的CTR1mRNA表达,Ⅰ-Ⅳ组光密度值分别为0.508±0.035、0.391±0.022、0.240±0.023和0.186±0.021,呈下降趋势,各组间比较差异均有统计学意义（P〈0.05）。结论 CTR1在大鼠内耳有丰富的表达,其表达量可随鼓室内顺铂浓度增高而下降,且鼓室内给予硫酸酮其表达量下降。

Objective To study the expression of copper transport protein 1in the inner ear of rat and the changes of CTR1 expression after those round window niche copper sulfate and cisplatin infusion.Methods 24 male wistar rats were randomly divided into 4groups：Group I as the normal control group（nontreatment group）;Group II as the round window niche cisplatin infusion group（0.5mg/ml）;Group III as the round window niche cisplatin infusion group（1mg/ml）;group IV as the round window niche copper sulfate infusion（0.02mg/kg）.The CTR1 protein was detected by the immunohistochemical（IHC）otaining and Western-blot,and the CTR1 mRNA expression levels were detected by RT-PCR.Results The expression of CTR1 protein was observed in the cytoplasm and cell membrane of Corti organ cells,spiral ganglion cells and stria vascularis in all groups.The average optical densities of CTR1 protein was a downward trend.The expression of CTR1 protein was observed in four different groups.The optical density analysis of CTR1 showed that the optical densities were 0.532±0.031,0.394±0.024,0.234±0.030 and 0.191±0.015,respectively.There was a downward trend,and there were statistically differences among the groups（P〈0.05）.The CTR1 mRNA was observed in all groups.The optical density analysis of CTR1mRNAshowed that the optical densities were 0.508±0.035,0.391±0.022,0.240±0.02 and 0.186±0.021,respectively.It had a downward trend and were statistically differences among the groups（P〈0.05）.Conclusion The CTR1 protein was abundantly expressed in Corti organ,spiral ganglion cells and stria vascularis of the cochlea.The round window cisplatin and copper sulfate infusion can change the expression of CTR1 proteins in inner ear.