Oculomotor plasticity during vestibular compensation does not depend on cerebellar LTD
Oculomotor plasticity during vestibular compensation does not depend on cerebellar LTD
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DOI：
10.1152/jn.00045.2006
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发表时间：
2006-09-01
影响因子：
2.5
通讯作者：
De Zeeuw, C. I.
中科院分区：
文献类型：
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作者：
Faulstich, M.;van Alphen, A. M.;De Zeeuw, C. I.
前庭范式被广泛用于研究小脑运动学习的机制。这些包括视觉-前庭失配训练后前庭眼反射（VOR）的适应和前庭器官单侧损伤后的前庭补偿。迄今为止，各种研究表明，VOR适应可能是由平行纤维到浦肯野细胞突触的长期抑制（LTD）支持的。然而，前庭补偿在多大程度上依赖于这种细胞过程还不清楚。在这里，我们研究了自适应增益变化的VOR和视动反射在前庭补偿的转基因小鼠，其中LTD是专门阻止浦肯野细胞通过表达的蛋白激酶C（L7-PKCi突变体）的肽抑制剂。结果表明，无论是强度，也不是前庭补偿的时间过程的影响，没有有限公司。相反，分析前庭补偿自发突变体，缺乏功能性橄榄-小脑电路（lurchers）表明，这种形式的运动学习严重受损。我们的结论是，前庭补偿过程中的眼可塑性严重依赖于完整的小脑电路，但不是小脑LTD的发生。
Vestibular paradigms are widely used for investigating mechanisms underlying cerebellar motor learning. These include adaptation of the vestibuloocular reflex (VOR) after visual-vestibular mismatch training and vestibular compensation after unilateral damage to the vestibular apparatus. To date, various studies have shown that VOR adaptation may be supported by long-term depression (LTD) at the parallel fiber to Purkinje cell synapse. Yet it is unknown to what extent vestibular compensation may depend on this cellular process. Here we investigated adaptive gain changes in the VOR and optokinetic reflex during vestibular compensation in transgenic mice in which LTD is specifically blocked in Purkinje cells via expression of a peptide inhibitor of protein kinase C (L7-PKCi mutants). The results demonstrate that neither the strength nor the time course of vestibular compensation are affected by the absence of LTD. In contrast, analysis of vestibular compensation in spontaneous mutants that lack a functional olivo-cerebellar circuit (lurchers) shows that this form of motor learning is severely impaired. We conclude that oculomotor plasticity during vestibular compensation depends critically on intact cerebellar circuitry but not on the occurrence of cerebellar LTD.