与咬肌运动神经元直接联系的运动前神经元在脑干的分布

目的为了定位向咬肌运动神经元投射的最后一级运动前神经元在脑干内的分布。方法注射麦芽凝集素结合的辣根过氧化物酶(WGA-HRP)至咬肌神经逆行跨突触追踪,然后通过免疫组织化学方法显示了该类神经元。结果这类神经元分布在双侧三叉上核(Vsup)、三叉神经感觉主核背侧部(Vpdm)、小细胞网状结构(PCR)和三叉神经脊束核吻侧亚核背侧部(Vodm),以及对侧三叉神经运动核(Vmo)。数量上,Vsup,特别是注射侧Vsup中,标记的神经元数量最多;其他核团内,双侧标记的神经元的数量无明显差别。结论一侧咬肌运动神经元直接接受脑干双侧多个区域调控。

DISTRIBUTION OF PREMOTOR NEURONS SYNAPSING ONTO MASSETER MOTONEURONS IN THE BRAINSTEM

Objective To investigate the distribution of the last order premotor neurons of masseter motoneurons which synapse onto the brainstem.Methods Horseradish peroxidase coupled to wheat germ lectin(WGAHRP) was injected into the masseter nerve for transsynaptic labeling of premotor neurons,and then the labeled neurons were showed by immunostaining.Results The last order premotor neurons of masseter motoneurons were located bilaterally in supratrigeminal(Vsup),dorsomedial part of the principal sensory trigeminal nucleus(Vpdm),dorsomedial part of the subnucleus oralis of the spinal trigeminal nucleus(Vodm) andthe parvicellular reticular formation(PCR),and contralaterallyin the trigeminal motor nucleus(Vmo).Conclusion Masseter motorneurons are innervated bilaterally by premotor neurons extensively distributed in several nuclei of the brainstem.