慢性锰中毒对大鼠听功能及耳蜗细胞的影响  

Effects of Chronic Manganism on Hearing and Cochlear Cells in Rats

作　　者：唐晓旭[1,2] 丁忠家 王人凤[1] 施泽涛[1] 邢蔚[1] 闫辉[1] 武瑾[1] 宋勇莉[1] 卢连军[1] 

机构地区：[1]第四军医大学西京医院耳鼻咽喉头颈外科,西安710032 [2]解放军后勤学院门诊部

出　　处：《听力学及言语疾病杂志》2014年第3期281-285,共5页Journal of Audiology and Speech Pathology

基　　金：国家自然科学基金项目(H2602H2607)

摘　　要：目的探讨锰中毒对大鼠听功能及耳蜗毛细胞、螺旋神经节细胞的影响。方法选取60只断乳21天的SD大鼠,随机分为染毒组和对照组,染毒组(30只)给予氯化锰水溶液(MnCl2·4H2O,100mg·kg-1d-1)连续灌胃12w,对照组(30只)以同法给予等量去离子水。于灌胃4、8和12w后分别检测两组大鼠血锰浓度,于灌胃12w对两组大鼠分别行ABR检测,基底膜铺片鬼笔环肽-异硫氰酸荧光素(Phalloidin-FITC)染色观察毛细胞形态及计数,HE染色观察螺旋神经节细胞形态及计数,透射电镜观察毛细胞及螺旋神经节细胞超微结构的变化。结果染毒组大鼠灌胃4、8、12w后血锰浓度分别为24.1±2.4、31.5±2.6、26.7±2.8ng/ml,明显高于对照组(分别为8.5±1.7、11.2±2.1、12.7±2.1ng/ml),差异有统计学意义(均为P<0.05)。灌胃12w后,染毒组大鼠4、8、16、24、32kHz ABR反应阈均明显高于对照组(P<0.05),其中高频阈值升高显著。灌胃12w后,染毒组耳蜗毛细胞缺失,以底回缺失明显;螺旋神经节细胞数量减少;毛细胞和螺旋神经节细胞线粒体嵴断裂或消失,呈空泡样变。结论慢性锰中毒可导致大鼠耳蜗毛细胞缺失和螺旋神经节细胞减少,进而导致大鼠听功能损伤。Objective To study the effects of chronic manganism on hearing and cochlear cells in rats by using animal model of chronic manganism .Methods Sixty adult SD rats were randomly divided into Mn - exposed and controlgroups.RatsweretreatedwithMnCl24H2O（100mg·kg ^-1·d^-1）ordeionizedwaterbygastricperfusion, lasted for 12 weeks .The Mn concentration in peripheral blood was measured respectively at 4 weeks ,8 weeks and 12 weeks after treatment .At 12 weeks after treatment ,the auditory brainstem response was recorded ,the hair cells morphology and counting were examined by stretched preparation of basilar membrane stained with FITC -phalloi-din ,and the spiral ganglion cells morphology and counting were studied by HE staining ,the ultrastructure changes of hair cells and spiral ganglion cells were detected by transmission electron microscopy .Results The blood Mn concentration increased gradually with time after treatment .ABR thresholds at 4 ,8 ,16 ,24 and 32 kHz were sig-nificantly increased at 12 weeks after treatment ,especially in the high-frequency range .Morphological study at 12 weeks after treatment showed loss of outer hair cells ,mainly in the basal turn of the cochlea ,and decreased number of spiral ganglion cells .The ultrastructure changes of outer hair cells and spiral ganglion cells included the break -ups ,disappearance or vacuolar change of mitochondria cristas .Conclusion Our data demonstrate that chronic man-ganism can cause loss of outer hair cells and spiral ganglion cells in cochlear in rats ,leading to hearing loss .

关 键 词：锰中毒 毛细胞 螺旋神经节细胞 听力损失 

分 类 号：R764.5[医药卫生—耳鼻咽喉科]