Caston J, Delhaye-Bouchaud N, Mariani J
Laboratoire de Neurophysiologie Sensorielle, Université de Rouen, Mont-Saint-Aignam, France.
Behav Brain Res. 1995 Dec 14;72(1-2):97-102. doi: 10.1016/0166-4328(96)00137-4.
Three- to 24-month-old heterozygous staggerer (+/sg) and control (+/+) C57B16 mice were subjected to a motor test on a rota rod rotating at 30 or 40 revolutions per minute. The scores were evaluated by the time during which they maintained their equilibrium without falling down. Although the scores of both +/sg and +/+ animals decreased with age, the scores of +/sg mice were constantly lower at 3, 6 and 12 months and this difference was already significant at 3 months, i.e., before the 30% loss of Purkinje cells, granule cells and inferior olivary neurons which occurs between 3 months and 1 year in the mutant. At 18 months and beyond, scores no longer differed in both groups. These results show that there is no strict correlation between neuronal death in the cerebellar cortex and motor behavior on the rota rod. However, the difficulties in maintaining their equilibrium on the rota rod observed in +/sg mice as young as 3 months, indicate a deficit in accurate motor control which could be due to subtle structural or neurochemical disorders that probably precede neuronal death. Therefore, in the heterozygous staggerer, behavioral motor disturbance is a sign of cerebellar dysfunction which appears earlier than alterations in neuronal number.
对3至24月龄的杂合子蹒跚突变（+/sg）和对照（+/+）C57B16小鼠，在以每分钟30或40转旋转的转棒上进行运动测试。通过它们保持平衡不摔倒的时间来评估得分。尽管+/sg和+/+动物的得分均随年龄下降，但+/sg小鼠在3、6和12个月时的得分始终较低，且这种差异在3个月时就已显著，即在突变体3个月至1岁之间发生的浦肯野细胞、颗粒细胞和下橄榄核神经元损失30%之前。在18个月及以后，两组的得分不再有差异。这些结果表明，小脑皮质中的神经元死亡与转棒上的运动行为之间没有严格的相关性。然而，在年仅3个月的+/sg小鼠中观察到的在转棒上保持平衡的困难，表明精确运动控制存在缺陷，这可能是由于可能先于神经元死亡的细微结构或神经化学紊乱所致。因此，在杂合子蹒跚突变小鼠中，行为运动障碍是小脑功能障碍的一个迹象，其出现早于神经元数量的改变。
