Koekkoek S K, v Alphen A M, vd Burg J, Grosveld F, Galjart N, De Zeeuw C I
Department of Anatomy, Erasmus University Rotterdam, The Netherlands.
Genes Funct. 1997 Jun;1(3):175-90. doi: 10.1046/j.1365-4624.1997.00018.x.
The vestibulocerebellum is involved in the control of compensatory eye movements. To investigate its role in the learning and timing of motor behaviour, eye movements in normal and mutant mice were investigated for the first time with the use of search coils. Wild-type mice showed the ability to increase the gain of their vestibulo-ocular reflex by visuo-vestibular training. This adaptation did not occur in lurcher mice, a natural mouse mutant that completely lacks Purkinje cells. During the optokinetic reflex the phase (timing) of the eye movements of lurchers lagged behind that of wild-type littermates, whereas during the vestibulo-ocular reflex it led that of the wild types. Ablations of different parts of the vestibulocerebellum indicated that the flocculus is necessary for the adaptation and the phase-leading effects of the cerebellum, whereas the nodulus might contribute to its phase-lagging effects. We conclude that Purkinje cells in the vestibulocerebellum are necessary for both learning and timing of compensatory eye movements in mice, and that the flocculus and nodulus may play antagonistic roles in these processes. The present description of the basic principles of cerebellar eye-movement control opens up the possibility to investigate the mechanisms of this motor behaviour at the molecular level in genetically manipulated mutant mice.
前庭小脑参与代偿性眼球运动的控制。为了研究其在运动行为学习和定时中的作用，首次使用搜索线圈对正常小鼠和突变小鼠的眼球运动进行了研究。野生型小鼠表现出通过视觉-前庭训练增加其前庭眼反射增益的能力。这种适应性变化在完全缺乏浦肯野细胞的自然小鼠突变体——蹒跚小鼠中并未发生。在视动反射期间，蹒跚小鼠眼球运动的相位（定时）落后于野生型同窝小鼠，而在前庭眼反射期间，其相位则领先于野生型小鼠。对前庭小脑不同部位的切除表明，绒球对于小脑的适应性变化和相位领先效应是必需的，而小结可能对其相位滞后效应有贡献。我们得出结论，前庭小脑中的浦肯野细胞对于小鼠代偿性眼球运动的学习和定时都是必需的，并且绒球和小结在这些过程中可能发挥拮抗作用。目前对小脑眼球运动控制基本原理的描述为在基因操作的突变小鼠中从分子水平研究这种运动行为的机制开辟了可能性。
