Wang Han-Zhi, Li Shu-Rong, Wen Can, Xiao Chuan-Guo, Su Bing-Yin
Department of Neurobiology, Third Military Medical University, Chongqing 400038, China.
Neurosci Bull. 2007 Sep;23(5):277-81. doi: 10.1007/s12264-007-0041-y.
To establish an artificial somatic-autonomic reflex arc in rats and observe the following distributive changes of neural fibers in the bladder.
Adult Sprague-Dawley rats were randomly divided into three groups: control group, spinal cord injury (SCI) group, and reinnervation group. DiI retrograde tracing was used to verify establishment of the model and to investigate the transport function of the regenerated efferent axons in the new reflex arc. Choline acetyltransferase (ChAT) in the DiI-labeled neurons was detected by immunohistochemistry. Distribution of neural fibers in the bladder was observed by acetylcholine esterase staining.
DiI-labeled neurons distributed mainly in the left ventral horn from L3 to L5, and some of them were also ChAT-positive. The neural fibers in the bladder detrusor reduced remarkably in the SCI group compared with the control (P < 0.05). After establishment of the somatic-autonomic reflex arc in the reinnervation group, the number of ipsilateral fibers in the bladder increased markedly compared with the SCI group (P < 0.05), though still much less than that in the control (P < 0.05).
The efferent branches of the somatic nerves may grow and replace the parasympathetic preganglionic axons through axonal regeneration. Acetylcholine is still the major neurotransmitter of the new reflex arc. The controllability of detrusor may be promoted when it is reinnervated by the pelvic ganglia efferent somatic motor fibers from the postganglionic axons.
在大鼠体内建立人工体-自主神经反射弧，并观察膀胱神经纤维的分布变化。
将成年Sprague-Dawley大鼠随机分为三组：对照组、脊髓损伤（SCI）组和再支配组。采用DiI逆行追踪法验证模型的建立，并研究新反射弧中再生传出轴突的运输功能。通过免疫组织化学检测DiI标记神经元中的胆碱乙酰转移酶（ChAT）。采用乙酰胆碱酯酶染色观察膀胱神经纤维的分布。
DiI标记的神经元主要分布在L3至L5左侧腹角，其中一些也是ChAT阳性。与对照组相比，SCI组膀胱逼尿肌中的神经纤维明显减少（P<0.05）。再支配组建立体-自主神经反射弧后，与SCI组相比，膀胱同侧纤维数量明显增加（P<0.05），但仍远低于对照组（P<0.05）。
体神经的传出分支可能通过轴突再生生长并替代副交感神经节前轴突。乙酰胆碱仍然是新反射弧的主要神经递质。当膀胱由盆神经节传出体运动纤维的节后轴突进行再支配时，逼尿肌的可控性可能会得到改善。
