体神经-内脏神经吻合后神经纤维再生过程的光镜电镜观察

目的：观察大鼠体神经-内脏神经吻合后神经纤维的再生。方法：人工建立体神经-内脏神经反射弧大鼠模型，用电镜配合光镜观察12只大鼠术后1、4、8、24周神经变性与再生。结果：术后8、24周大体观察见神经吻合口位置稍许膨大，光镜观察发现术后8周吻合口位置可见新生的轴突，电镜观察见术后1周吻合口及其远近段神经纤维发生Waller变性，术后4周吻合口部位有再生的有髓和无髓纤维，术后8周新生的髓鞘进一步增厚，板层结构清晰可见，术后24周，髓鞘成熟，轴浆富含微管、微丝、线粒体。结论：体神经运动纤维能够再生长入并替代内脏神经节前纤维；再生的神经纤维具备基本正常的周围神经超微结构。

Light microscope and electron microscope study of nerve regenerated procedure after somatic-autonomic nerve anastomosis

Objective The nerve regenerated procedure after somatic autonomic nerve anastomosis was investigated.Methods The somatic autonomic reflex arc rat model was established.The degener ated and regenerated procedure of the efferent nerve fibers were investigated under light microscope(LM) and electron microscope (EM) at 1,4,8,24 weeks postoperatively.Results The slight enlargement on the stoma site was observed at 8,24 weeks postoperatively.LM observation on the stoma site at 8th week after surgery showed regenerated axon.EM observation on the stoma site and its caudal and rostral segments at one week after surgery provided a typical picture of Waller degeneration.Regenerated myelinated and unmyelinated axons were discovered at stoma site at 4th week after anastomosis.At the 8th week,myelin sheath was thickened,and lamina structure were also observed.At the 24th week,regenerated nerve fibers had the structure of normal peripheral nerve with matured myelin sheath.The axoplasm contained abundant microtubule,microfilament and mitochondria.Conclusion Somatic motor nerve can regenerate into and replace autonomic preganglionic nerve fibers.The ultra structures of the regenerated nerve fibers are generally similar to those of the normal peripheral nerve.