摘要
目的观察噪声性聋小鼠耳蜗外侧壁缝隙连接蛋白Connexin26(Cx26)表达的变化。方法成年雄性Balb/c小鼠49只随机分为噪声组(29只)和对照组(20只)。实验前两组小鼠检测听性脑干反应(ABR),随后噪声组小鼠给予高强度噪声(115dB SPL,6小时/天,共2天12小时)暴露,并在噪声暴露后0和7天分别检测ABR。对照组不做任何处理。噪声暴露后4小时,每组取2只小鼠做耳蜗冰冻切片,18只小鼠提取耳蜗外侧壁总RNA。通过免疫组化染色法观察小鼠耳蜗外侧壁Cx26蛋白的表达,共聚焦显微镜下观察缝隙连接蛋白转运相关蛋白———β微管蛋白的表达,荧光实时定量PCR检测小鼠耳蜗外侧壁Cx26编码基因GJB2mRNA的表达。结果正常小鼠耳蜗螺旋韧带可见Cx26棕黄色阳性颗粒,血管纹处未见阳性表达;噪声组小鼠耳蜗外侧壁Cx26免疫组化染色较对照组减弱;Cx26编码基因GJB2mRNA表达量低于对照组,β微管蛋白排列稀疏紊乱,呈条索状排列,但未见明显浓集或断裂。结论噪声可下调小鼠耳蜗外侧壁Cx26的表达,Cx26可能参与了噪声性聋的发病机制。
Objective To investigate the expression of connexin26 in of mice cochlea lateral wall after noise exposure. Methods Forty-nine mice were randomly divided into 2 groups, there were 29 mice in noise group and 20 mice in control group, in which without noise exposure. The mice in noise group were exposed to wide band noise. The duration of sound exposure was 12 hours and 2 days at 115 dE SPL. After noise exposure, auditory brainstem response （ABR） in noise exposure group and control group were tested. Two mice＇ cochleas from each group were taken for frozen sectioning, and the rest cochlea were extracted for the total RNA of mice cochlea lateral wall. Expression of Cx26 protein was observed by immunohistochemistry staining. Expression of Cx26 mRNA was deteeted by real-time PCR. Expression of β-Tubulin protein was observed by confocal microscopy after immuno- fluorescence staining. Results Specific immunoreactive Cx26 was observed in spiral ligament （SPL）, but not in stria vascularis. Decreased Cx26 immunoreaction was observed in noise group compared to those of in control group. The level of GJB2 coding for Cx26 was reduced in noise group compared to those of in control group. Microtubules stained by B-tubilin were disordered after niose exposure, but no shattered. Conclusion Cx26 was present in mice cochlea lateral wall and was down regulated when ABR threshold shifted after noise exposure. Cx26 was involved in the pathogenesis of noised induced deafness.
出处
《听力学及言语疾病杂志》
CAS
CSCD
北大核心
2013年第3期263-266,共4页
Journal of Audiology and Speech Pathology
基金
国家自然科学基金资助(81100713)
