猫阴部神经传入传出成分在脊髓内的定位分布—HRP逆行及跨越神经节追踪研究

向猫阴部神经及其分支注入HRP溶液,观察并分析了逆行和跨节追踪的结果。 1.证实阴部神经为含躯体传出、传入,内脏传出、传入纤维的混合神经,其内脏性传出、传入成分仅存在于阴茎背神经中。 2.逆行标记细胞出现于L_7—S_3前角Onuf核和S_(1-3)的中间带外侧核。本文结果表明,Onuf核是支配盆底横纹肌的运动核,但它和其它前角运动核在细胞形态和活性物质的分布上都明显不同。特别是它的一部分神经元的树突形成树突束到达中间带外侧核。本文结合排尿、排便功能从形态学上较详细地讨论了Onuf核和中间带外侧核的关系。 3.本文证明阴部神经领域的内脏初级传入(来自阴茎背神经)和躯体初级传入纤维都向骶髓后连合核区有浓密的投射。结合以往的工作讨论了盆腔脏器、外生殖器的内脏传入和坐骨神经、阴部神经的躯体传入在骶髓后连合核区汇聚的现象及机能意义,推测这种汇聚可能是产生牵涉痛和针刺镇痛机制的形态学基础。

THE INTRASPINAL DISTRIBUTION OF THE AFFERENT AND EFFERENT ELEMENTS OF THE PUDENDAL NERVE IN THE CAT——A STUDY WITH THE HRP RETROGRADE AND TRANSGANGLIONIC TRACING METHODS

30％ HRP solution (Toyobo IC) was injected into the three branches of the pudendal nerve (10 cases) or one branch of it (9 cases) in different individuals of the cat. The retrograde and transgangtionic labeling was examined and the results were analysed.1. The present study demonstrated that the pudendal nerve was composed of both somatic and visceral fibers (both including efferent and afferent), and the visceral fibers were only contained in the nervus dorsalis penis.2. The retrogradely labeled neurons were observed in the Ounf's nucleus of the anterior horn in segments L7-S3 and in the intermediolateral nucleus in segments S1-3. The results of the present paper indicated that the neurons of the Onuf's nucleus innervate the striated muschs of the pelvic floer. But the form of the neurons and the active substances in the Onuf's nucleus was obviously different from other motor nuclei of of the anterior horn, especially in that the dendricic bundle formed by the dendrites of some neurons in Onuf's nucleus entered the intermediolateral nucleus. The morphological relaticns between the Onuf's nucleus and the intermediolateral nucleus were fully discussed in connection with the function of micturation and defecation.3. The present paper indicated that both somatic and visceral primary afferent fibers of the pudendal nerve projected densely onto the posterior commissural nucleus region of the sacral and caudal spinal cord. Combining the present results with those of the studies of other authors of our department, the author discussed the convergence of the visceral afferent fibers from the pelvic and the external genital organs and the somatic afferent fibers of the sciatic and pudendal nevres and its functional significance. It is presumed that this convergence might provide one of the structural basis for the referred pain and the neuronal mechanisms of acupunctural therapy.