人工反射弧建立后脊髓功能及形态改变的实验研究  

Change of the function and morphology of spinal cord in rat after the establishment of reflex pathway

作　　者：刘洋[1] 伍亚民[1] 刘媛[1] 龙在云[1] 曾琳[1] 李应玉[1] 杨恒文[1] 

机构地区：[1]第三军医大学大坪医院野战外科研究所三室创伤,烧伤与复合伤国家重点实验室,重庆市400042

出　　处：《中国脊柱脊髓杂志》2005年第12期744-748,i0018,共6页Chinese Journal of Spine and Spinal Cord

基　　金：国家重大基础研究发展规划(973)项目(编号:2003CB515304)重庆市院士基金(合同号:7671)

摘　　要：目的：观察“皮肤-脊髓-膀胱”人工反射弧建立后大鼠脊髓L4节段神经元单位放电及形态学改变情况。方法：32只SPF级Wistar成年雄性大鼠，均分为正常对照组和“皮肤-脊髓-膀胱”人工反射弧模型组，记录正常组和手术后3个月以上模型组大鼠L4节段背侧角和腹侧角的脊髓单位放电(SCUDs)以及在加入乙酰胆碱(ACh)和皮下电刺激的情况下SCUDs情况。同时对L4脊髓和膀胱组织行组织学检查。结果：模型组大鼠背侧角SCUDs的平均频率与正常组大鼠相比显著降低(P＜0．01)。在加入过量ACh(0．1mol／L)和连续电刺激(幅度7．6mA，持续200μs，频率4Hz)的情况下，模型组大鼠L4节段脊髓腹侧角SCUDs均受到抑制终止放电。脊髓L3尾部至L5头侧的左侧前角(以L4节段为主)可见NY单标的神经元，HE染色镜下观察模型组大鼠吻合门神经根纤维排列紊乱，细胞数量明显增多，有类血管样结构存存。左侧脊髓L4节段前角组织轻度萎缩，部分前角神经元胞浆皱缩，核深染，少量细胞出现空泡样变，部分细胞核边集。部分侧角中间神经元则形态较好。具有前角运动神经元的形态，膀胱壁一侧肌层增厚。结论：人工反射弧建立之后，部分中间神经元由于在功能上的可塑性可能替代部分萎缩的前角运动神经元的功能。乙酰胆碱可能参与了大鼠人工反射弧中L4脊髓节段腹侧角运动神经元网络的信息反馈过程。Objective：To observe the changes of spinal cord unit discharges （SCUDs） and morphology of L4 spinal cord as well as the bladder tissue in rats with the skin-CNS-bladder reflex pathway established. Method：The SCUDs of normal and model rats were recorded in anaesthetic condition.Then the changes of SCUDs were observe when the acetylcholine（ACh）（0.1M） was added to the surface of the L4 spinal cord and subcutaneous electric stimulation was added to the rat.At last the morphologic changes of L4 spinal cord and the bladder tissue were observed by light microscopy.Result：The average SCUDs＇ frequency of dorsal horn in model rats is remarkably slower than that of the normal rats（P〈0.01）.The average SCUDs＇ frequency of dorsal horn is notably slower than that of the ventral horn in model rats（P〈0.01）.The SCUDs of L4 spinal cord was observed blocked in model rats when the excessesive ACh（0.1M） was added to the surface of the L4 spinal cord or subcutaneous electric stimulus （amplitude 7.6mA,duration 200us,frequency 4Hz） was added.Nuclear yellow（NY） single labeled neurons were observed in locus of the left ventral horn from L3 caudal to L5 rostral.The fibers of microanastomosed ventral root were observed disorganized.The number of the cells increased. And the vascular structure were observed.Left ventral horn of L4 spinal cord displayed lightly atrophied.The cytoplasm of some neurons shrinked with the nuclear heavy stained.Few neurons were vacuole-liked.The nuclear of some ventral neurons was margined.The muscle layer of the bladder thickened. Conclusion：After the reflex pathway was established in rat,some of the interneurons＇ function may be changed to substitute the function of those located in the ventral horn of the L4 spinal cord because of their functional plasticity.ACh may be involved in the process of the informational feedback of L4 spinal cord in rat.

关 键 词：人工反射弧 脊髓单位放电 大鼠 

分 类 号：R683.2[医药卫生—骨科学] Q426[医药卫生—外科学]