Hair cell regeneration and recovery of the vestibuloocular reflex in the avian vestibular system
Hair cell regeneration and recovery of the vestibuloocular reflex in the avian vestibular system
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DOI：
10.1152/jn.1996.76.5.3301
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发表时间：
1996-11-01
影响因子：
2.5
通讯作者：
Rubel, EW
中科院分区：
文献类型：
--
作者：
Carey, JP;Fuchs, AF;Rubel, EW
1.虽然已知鸟类的听觉和前庭毛细胞在氨基糖苷类药物中毒后会再生，但只有很少的证据表明再生的毛细胞具有功能。为了解决这个问题，我们研究了毛细胞再生的前庭眼反射（VOR），其传入信号起源于前庭上皮毛细胞的恢复的关系。通过用硫酸链霉素的生理盐水（1，200 mg . kg（-1）。第（-1）天，肌肉注射）5天。在治疗后的第1周，VOR增益基本上为O，通过光学显微镜评估的毛细胞密度与正常的40%相似。在治疗后第1和第3周之间，VOR存在。虽然VOR增益从一只鸡到另一只鸡变化很大，它增加，平均，第1和第3周之间，平均毛细胞密度。8-9 wk时，VOR的增益和相位已恢复正常，毛细胞的平均密度也恢复正常.因此，尽管毛细胞损失对VOR的灾难性的初始影响，恢复的毛细胞似乎完全恢复VOR。平均毛细胞密度随VOR增加而增加。VOR增益与I型毛细胞恢复的相关性优于与II型毛细胞恢复的相关性.与毛细胞密度相比，在扫描电镜下通过毛细胞静纤毛评估前庭上皮的外观是VOR增益的不良指标。在处理组和对照组中，具有相同外观的上皮细胞可能具有完全不同的VOR增益，这表明毛细胞的功能活力存在差异。这一观察结果表明，几个因素，如静纤毛的修复，传入纤维的毛细胞突触的功效，以及中央前庭通路的补偿程度，可能会影响VOR增益的恢复。然而，我们的数据表明，毛细胞再生在这种恢复中起着重要作用。
1. Although auditory and vestibular hair cells are known to regenerate after aminoglycoside intoxication in birds, there is only sparse evidence that the regenerated hair cells are functional. To address this issue, we examined the relation of hair cell regeneration to recovery of the vestibuloocular reflex (VOR), whose afferent signal originates at hair cells in the vestibular epithelium. Hair cell damage was produced by treating white Leghorn chicks (Gallus domesticus, 4-8 days posthatch) with streptomycin sulfate in normal saline (1,200 mg . kg(-1). day(-1) im) for 5 days.2. In the 1st wk after treatment, the VOR gain was essentially O, and hair cell density as assessed by light microscopy was similar to 40% of normal. Between the Ist and 3rd wk after treatment, the VOR was present. Although VOR gain varied considerably from one chick to another, it increased, on average, between the 1st and 3rd wk, as did the average hair cell density. At the end of 8-9 wk, the gain and phase of the VOR had returned to normal values, as had the average density of hair cells.3. Therefore, despite the catastrophic initial effect of hair cell loss on the VOR, recovered hair cells appeared to restore the VOR completely. Average hair cell density increased with average VOR gain. VOR gain correlated better with recovery of type I hair cells than with recovery of type II hair cells.4. Ln contrast to hair cell density, the appearance of the vestibular epithelia as assessed by hair cell stereocilia in scanning electron micrographs was a poor indicator of VOR gain. In both treated and control birds, epithelia with the same appearance could have quite different VOR gains, suggesting a variation in the functional viability of the hair cells.5. This observation suggests that several factors, such as the repair of stereocilia, the efficacy of hair cell synapses on afferent fibers, and the extent of compensation by central vestibular pathways, may affect the recovery of VOR gain. However, our data suggest that hair cell regeneration plays an important role in this recovery.