人胚胎三叉神经节神经元的躯体定位

目的:应用1,1′-双十八烷-3,3,3′,3′-四甲基吲哚羰花青-高氯酸盐(DiI)追踪技术研究人胚胎发出眼神经、上颌神经及下颌神经的神经元在三叉神经节内的解剖定位.方法:对胎龄20周以上的6个胎儿标本进行灌注固定后,分别于标本的眼、上颌、下颌神经处植入DiI染色晶体.37℃恒温箱放置3个月,等待DiI染色晶体扩散,再根据神经走向切片,荧光显微镜下观察发出3支神经的神经元在三叉神经节内的解剖定位.结果:人胚胎三叉神经节是沿内外方向分布的细胞团.发出眼神经的神经元位于神经节的前内侧,下颌神经的神经元位于神经节的后外侧,上颌神经的神经元位于两者之间.结论:人胚胎发出眼神经、上颌神经及下颌神经的神经元在三叉神经节内以内外局部定位方式排列.

Somatotopic organization of trigeminal ganglion neurons in human fetus

Objective: To investigate the localization of neuronal cells originating from the ophthalmic nerve, maxillary nerve and mandibular nerve in human fetus by 1, 1 '-dioctadecyl-3, 3, 3', 3'-tetramethylin-docarbocyanine perchlorate (Dil) within the trigeminal ganglion. Methods: Dil was embedded into the ophthalmic nerve, maxillary nerve and mandibular nerve in fixed postmortem human tissues of 6 fetuses. The tissue was incubated at 37℃ for 3 months, and then sectioned, mounted and observed under a fluorescence microscope after Dil had satisfactorily diffused. Results:The cells in the trigeminal ganglion of human fetus originating branches were arranged in the medio-lateral direction. Namely, the ophthalmic ganglion cells were distributed in the anterio-median part of the ganglion. The mandibular ganglion cells were distributed in the posterio-lateral part of the ganglion. The maxillary ganglion cells were distributed in the intermediant part between the cells originating the ophthalmic and mandibular branches. Conclusion:The cells in the trigeminal ganglion have been considered to be organized somatotopically in a medio-lateral direction reflecting the medio-lateral order of the three primary nerve branches (ophthalmic nerve, maxillary nerve and mandibular nerve).