周围神经嵌压后脱髓鞘改变的实验研究

EXPERIMENTAL STUDY OF DEMYELINATION OF PERIPHERAL NERVE COMPRESSION

目的：探讨周围神经嵌压后脱髓鞘改变与压力的关系。方法：新西兰大白兔２０只（４０条坐骨神经），按压力大小分为０、４、８、１２ｋＰａ（１ｋＰａ＝７．５ｍｍＨｇ）４组。将坐骨神经从神经压迫器的孔隙内通过，持续加压１小时后解除压迫，术后１周取坐骨神经受压段及其远端行横、纵断切片和神经单丝纤维撕梳，在光镜和电镜下行组织形态学观察。结果：各压力组神经受压段发生不同程度的节段性脱髓鞘改变；压力升高其病理改变则加重，受压神经段和气囊两端的神经纤维水肿和脱髓鞘改变较重，粗神经纤维较细神经纤维损伤重；神经的外周区较中心区脱髓鞘明显；神经的远端脱髓鞘不明显。结论：神经受压后呈节段性脱髓鞘，其程度与压力成正比，受压神经的远端脱髓鞘不显著。

Objective:To study demyelination of experimental compression lesions of peripheral nerves Methods:Acute graded nerve compression was applied to the sciatic nerves of 20 adult rabbits in whom an inflatable miniature. Plexiglas compression device had been implanted in the both side thigh The external pressure of 0、4、8、12 kPa were used to compress nerves for 1 hour Nerves were excised at 7 days,and 2 μm thickens transverse sections and teased fibers were made. Results:The pathologic change were nerve edema and demyelination which were observed at all pressure points Demyelination was the predominant lesion in nerves subjected to pressure and was commonly present in nerves around which the compression chamber remained uninfleated Demyelination of nerves which far from the compression chamber was Conclusions:The experiment showed that segment demylination and edema occurred at the position of nerves be compressed;The degrade of demylination was in right proportion to presser,the demylination was unremarkable far from the injured position of nerves