卡铂损害灰鼠前庭神经元和前庭Ⅰ型毛细胞的定量观察

Carboplatin-induced Vestibular Damage:Quantitative Measurement of Type I Hair Cell Loss and Ganglion Cell Loss

目的 定量观察卡铂对前庭神经系统的破坏作用 ,将前庭毛细胞的病变与前庭神经元的病变进行对比和分析 ,同时探讨其与卡铂引起的前庭性诱发眼球震颤持续时间改变的关系。方法 应用微量冰水诱发前庭性眼球震颤以观察前庭功能的改变。应用前庭终器取材料和铺片技术以及前庭终器小视野定量观察方法进行毛细胞密度的测量以证明毛细胞的损失程度。应用连续切片和神经元计数技术定量观察前庭神经元的损害。上述三项指标用于正常和卡铂耳中毒灰鼠动物模型的观察。结果 卡铂耳中毒灰鼠的前庭诱发眼震持续时间明显缩短 ;卡铂造成两个囊斑微纹区和壶腹嵴顶部的前庭Ⅰ型毛细胞缺损严重 ,但周边区毛细胞损失程度较轻 ,前庭Ⅱ型毛细胞则无明显损害 ;卡铂造成前庭神经元的数量明显减少 ,其损失程度与Ⅰ型毛细胞的损失程度相接近。结论 卡铂选择性破坏灰鼠前庭Ⅰ型毛细胞及其支配神经节 。

Objective The aim of the study was to quantitatively compare the loss of vestibular hair cells versus that of vestibular ganglion cell and to relate these anatomical changes to the durations of vestibular nystagmus.Methods Chinchillas were treated with carboplatin to selectively damage type Ⅰ vestibular hair cells and vestibular ganglion neurons.Vestibular nystagmus induced by caloric stimulation was evaluated and compared to quantitative measurements of vestibular hair cell and ganglion cell loss.Results 1.The duration of vestibular nystagmus was significantly reduced after carboplatin treatment.2.Carboplatin treatment resulted in a significant loss of type I hair cells in the striolar region of the macula in saccule and utricle and in the apical surface of the crista ampularis;however,type Ⅱ hair cells and hair cells in the marginal regions of the sensory epithelium remained normal.3.Carboplatin treatment caused a significant reduction in vestibular ganglion neuron;the amount of ganglion cell loss was similar to the hair cell loss.Conclusion Carboplatin selectively destroys type I hair cells and ganglion cells in the vestibular system and the loss of these cells is correlated with a reduction in vestibular nystagmus.