L型电压门控钙通道α1D亚基在内耳毛细胞的分布及在听力中的作用  

Expression of L-type Voltage-gated Calcium Channel α_1D Subunit in Inner Ear Hair Cell and Its Correlation with Hearing

作　　者：褚汉启[1] 宋海涛[2] 周良强[1] 黄孝文[1] 甄宏韬[1] 高起学[1] 崔永华[1] 

机构地区：[1]华中科技大学同济医学院附属同济医院耳鼻咽喉科,武汉430030 [2]卫生部北京医院耳鼻咽喉科

出　　处：《听力学及言语疾病杂志》2007年第1期37-40,I0001,共5页Journal of Audiology and Speech Pathology

基　　金：国家自然科学基金资助项目(编号30371526)

摘　　要：目的探讨L型电压门控钙通道α1D亚基在内耳毛细胞的分布及在听力中的作用。方法应用免疫细胞化学荧光标记观察L型电压门控钙通道α1D亚基在牛蛙毛细胞上的分布;利用听性脑干反应(ABR)检测携带不同L型电压门控钙通道α1D基因型(α1D+/+、α1D+/-和α1D-/-)小鼠的听力。结果L型电压门控钙通道α1D亚基主要密集分布于毛细胞侧膜和顶膜,在毛细胞的胞核区域和纤毛丛处没有阳性荧光染色。三种α1D基因型小鼠的ABR检测结果显示,α1D+/+野生型小鼠的短声反应阈正常,为34.8±5.7dBSPL;α1D+/-杂合子小鼠反应阈高于同窝生α1D+/+野生型小鼠,为54.4±12.4dBSPL;α1D-/-小鼠呈现全聋,ABR在100dBSPL时仍无反应。结论L型电压门控钙通道的α1D亚基分布在牛蛙毛细胞的侧膜和顶膜,在内耳的听觉生理中具有重要作用。L型电压门控钙通道α1D亚基缺失或是数量的减少均可以影响小鼠听力。Objective To investigate the expression and distribution L- type voltage - gated calcium channel subunit α1D in inner ear hair cell of bullfrog and its correlation with mice hearing. Methods Laser scanning confocal microscope combined with immune - fluroscence cytochemistry to determine the expression of L- type voltage - gated calcitum channel α1 D subunit in inner ear hair cell of bullfrog.Auditory bminsteem response（ABR） were measured in α1D^-/- ,α1D^＋/- and α1D^＋/＋ mice to determine the hearing threshold of mice. Results L- type voltage - gated calcium channel at D subunit staining was localized in the lateral wall membrane,apical membrane of the hair cen. No staining was observed in hair bundles of hair cell. The auditory function of α1D^＋/＋ mice was nomad, the mean value for ABR thresholds in response to click sound stimulus was 34.8±5,7 dB SPL. The mean value for ABR thresholds in response to click sound stimulus was elevated in α1D^＋/- mice at 54.4±12.4 dB SPL. Relative to that observed in α1D^＋/＋ mice,it was significantly increased（ P 〈 0.05）.α1D^-/- mice were completely deaf without observable ABR wave even at 100 dB SPL sound stimuli. Conclusion L - type voltage - gated calcitum channel α1D subunit appeares on lateral membrane,apical membrane of hair cell of bullfrog and plays a critical role in calcium role in the inner ear hair cell.Lacking of L- type voltage- gated calcium channel α1D subunit will affect the auditory function of the animal.

关 键 词：内耳 毛细胞 电压门控性钙通道 听力 

分 类 号：R339.16[医药卫生—人体生理学]