Terashima T, Kishimoto Y, Ochiishi T
Department of Anatomy, Tokyo Metropolitan Institute for Neuroscience, Japan.
Brain Res. 1994 Dec 12;666(1):31-42. doi: 10.1016/0006-8993(94)90279-8.
We examined the musculotopic organization in the motor trigeminal nucleus and the somatotopical arrangement in the trigeminal ganglion of the normal and reeler mice. To determine whether or not masticatory motoneurons are malpositioned in the reeler mouse, we injected horseradish peroxidase (HRP) into the masticatory muscles of normal and reeler mice. Injections of HRP into the jaw-closing muscles, i.e., the masseter and temporalis muscles, labeled large multipolar neurons in the dorsolateral division of the motor trigeminal nucleus of both normal and reeler mice. Similar injections into the jaw-opening muscles, i.e., the anterior belly of the digastric muscle and mylohyoid muscle, labeled large multipolar neurons in the ventromedial division of the motor trigeminal nucleus of both mouse strains. Thus, the normal myotopical arrangement of the masticatory muscles on the motor trigeminal nucleus is preserved in the reeler mouse. However, detailed analysis revealed that jaw-opening motoneurons were more widely scattered in the reeler mouse than in the normal control. To examine the somatotopical arrangement of the first-order sensory neurons in the trigeminal ganglion of the normal and reeler mice, we subcutaneously injected Fast blue (FB) into the mental region and Diamidino yellow (DY) into the vibrissal region of the same animals. No differences in distribution patterns of FB-labeled and DY-labeled neurons in the whole-mounted trigeminal ganglion could been seen between these two strains, suggesting that migration of trigeminal ganglion cells, which are derived from the neural crest and placode, is not deranged by the reeler genetic locus.
我们研究了正常和reeler小鼠运动三叉神经核中的肌位组织以及三叉神经节中的躯体定位排列。为了确定reeler小鼠中咀嚼运动神经元的位置是否异常，我们将辣根过氧化物酶（HRP）注入正常和reeler小鼠的咀嚼肌中。将HRP注入闭口肌，即咬肌和颞肌，标记了正常和reeler小鼠运动三叉神经核背外侧部的大型多极神经元。对张口肌，即二腹肌前腹和下颌舌骨肌进行类似注射，标记了两种小鼠品系运动三叉神经核腹内侧部的大型多极神经元。因此，reeler小鼠保留了咀嚼肌在运动三叉神经核上正常的肌位排列。然而，详细分析显示，reeler小鼠中的张口运动神经元比正常对照中的分布更广泛。为了研究正常和reeler小鼠三叉神经节中一级感觉神经元的躯体定位排列，我们将快蓝（FB）皮下注射到同一动物的颏部区域，将双脒基黄（DY）注射到触须区域。在这两种品系的整装三叉神经节中，未观察到FB标记和DY标记神经元的分布模式存在差异，这表明源自神经嵴和基板的三叉神经节细胞的迁移未受reeler基因位点的干扰。
