经家兔肠系膜下节的内脏传入神经元的节段性分布——HRP法研究

THE SEGMENTAL DISTRIBUTION OF NEURONS OF THE VISCERAL AFFERENT TRAVERSING THE INFERIOR MESENTERIC GANGLION OF THE RABBIT——HRP STUDY

将HRP注入8只家兔的肠系膜下节内,观察内脏传入神经元的胞体在脊神经节的分布节段,结果如下。标记细胞分布在双侧的T_(11)-L_(6)脊神经节,89.83%的标记细胞集中分布在L_(1)—L^(4)节段,其中以L_(3)最多,占标记细胞总数的29.67%。向颅、尾侧逐渐减少,表明内脏感觉经交感途径的传入节段既有弥散又有相对集中的特点。此外,路经家兔肠系膜下节的传入神经元与支配该节的节前神经元在分布节段上存在着对应关系,这种对应关系可能为内脏活动的反射通路提供了形态学证据。左、右侧脊神经节内标记细胞的数量相差不多。标记细胞的基本形态为圆形或椭圆形,97.66%的标记细胞为50μm以下的中、小型细胞。

HRP was injected into the inferior mesenteric ganglia of eight rabbits to observe the labelled visceral afferent neurons in spinal ganglia and their segmental distribution. The results were as follows:The labelled cells were distributed bilaterally in the spinal ganglia of the T11-L6 segments, but 89.83% of them were accumulated in the L1-L4 ganglia, with the largest number in L3(29.67% of the total). The number of the labelled cells in the spinal ganglia guadually decreased cranially and caudally. It was shown that the visceral afferent s via sympathetic system were not only diffusely arranged but also relatively concentrated in certain segments. The amount of the labelled cells in the left spinal ganglia is almost equal to that of the right. Further more, the segmental distribution of the afferent neurons traversing the inferior mesenteric ganglion just corresponded to that of the sympathetic preganglionic neurons innervating the same ganglion, which might provide themorphological evidence for the intrasegmental reflex pathway of the viseral activity.The labelled cells were round or oval in shape and medium or small in size. 97.66% of the labelled cells were less than 50μm in diameter.