摘要
目的建立变态反应性脱髓鞘模型,观察其听力学改变和耳蜗及听神经的病理变化。方法选取Wistar大鼠100只,随机分为模型组、对照组和正常组,分别皮下注射牛坐骨神经髓鞘碱蛋白、完全弗氏佐剂和生理盐水;对所有实验动物在免疫前、免疫结束后1、2、3、4、5、6周进行听性脑干诱发电位、耳声发射检查。各组随机抽取2只动物,2.5%戊二醛活体灌注后处死,电镜下观察听神经末梢突触间隙的变化。结果髓鞘碱蛋白免疫后的动物共37耳/20只成为模型动物,听神经近中枢段在给药后1周均出现脱髓鞘病变,给药后第3周达到高峰,随后自行缓解,在第6周基本恢复;神经末梢和毛细胞突触间隙结构上无明显变化;模型动物听性脑干诱发电位阈值在实验第1周时增高,然后逐渐恢复;Ⅲ波潜伏期在实验第1周时延长,实验期间无明显恢复;畸变产物耳声发射给药1周后于0.5、1.0、2.0 kHz降低,瞬态耳声发射给药1周后所有频率均降低。结论免疫性脱髓鞘模型有听神经近中枢端脱髓鞘改变和毛细胞损伤,其听力学改变和听神经病不同。
Objective To establish a model of allergic demyelination, observing changes in audiology and inner ear pathology, and to explore the pathological changes in auditory neuropathy. Methods 100 Wistar rats were randomly divided into model group, the control group and normal group in order to establish the animal model of autoimmune demyelination by heterologous myelin basic protein of peripheral nerve and complete freunds adjuvant. In the control group, antigen was replaced by the complete freunds adjuvant and there was 0.9% saline in the normal group. Auditory brainstem response audiometery, otoacoustic emission were assayed weekly before and after immunization for a period of seven weeks. Every week two rats from each group were killed randomly to observed pathological changes in auditory nerve and cochler. Results The auditory nerve in model group suffered from demyelinating lesions in the first week after delivery and the suffering reached the peak after three weeks. It could be self relieved and get a basic recovery in 6 weeks; there were no significant changes in the synaptie cleft between the inner hair cells and auditory nerve fibers. The auditory brainstem response audiometery threshold response increased from the range of 10 to 25 dBnH1 in 37/120 ears in the model group, and latency of wave？prolonged in hearing loss group. For those rats, the amplitude of distortion product otoacoustic emissions reduced at 0.5, 1.0, 2.0 kHz of the hearing loss animals, and transient evoked otoacoustic emissions had same changes at all frequencies. Conclusion The immune demyelinating model has part of auditory nerve demyelination and injury of inner hair cells and its audiological changes are different from those of auditory neuropathy.
出处
《兰州大学学报（医学版）》
CAS
2011年第1期39-43,共5页
Journal of Lanzhou University（Medical Sciences）
基金
甘肃省自然科学基金(0710RJZA035)
关键词
听神经病
脱髓鞘疾病
诱发电位
auditory neuropathy
demyelinating diseases
evoked potential
