Chuan-Guo Xiao

Nogo-A Expresses on Neural Stem Cell Surface

ABSTRACT Nogo-A, as a myelin-associated molecule to inhibit axon regeneration in the injured adult central nervous system (CNS), has been detected to be enriched in numerous populations of cells in CNS. In this study, we found that Nogo-A was also expressed on the surface of neural stem cells (NSCs). The possible effects of NSCs-expressed Nogo-A on the NSC transplantation for CNS repair were discussed.

Morphological changes of cholinergic nerve fibers in the urinary bladder after establishment of artificial somatic-autonomic reflex arc in rats

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. 观察体神经, 内脏神经人工反射弧建立后?大鼠膀胱肌间神经丛分布的改变以及神经肌肉接头处的变化。 Sprague-Dawley 大鼠随机分为三组: 对照组、 脊髓横断组和手术重建组。 手术重建组大鼠术后饲养 3 个月, 与脊髓横断组大鼠一起进行脊髓横断, 再继续饲养3 个月, 对照组不做任何处理。 DiI 进行逆行神经追踪; 免疫荧光的方法显示 DiI 阳性标记细胞中的胆碱乙酰转移酶(choline acetyltransferase, ChAT); 改良的 Karnovsky-Roots法 检测膀胱铺片中神经纤维的分布。 DiI 阳性标记细胞主要分布于脊髓 L3 尾部至 L5 头侧前角, ChAT 阳性细胞和 DiI 阳性标记细胞部分重叠。 手术重建组和对照组相比, 膀胱肌间神经纤维的数量较少, 染色浓度也较浅(P < 0.05); 而手术重建组神经纤维密度较脊髓横断组增大, 染色浓度增强(P < 0.05); 且出现明显的神经再分布。 人工体内脏神经反射弧建立后, 新的传出支为体神经, 可以长入副交感神经纤维, 传出神经元的递质仍为乙酰胆碱, 膀胱内胆碱能神经纤维再生和乙酰胆碱活性增强且出现神经再分布, 这可能在膀胱的控制性排尿中起作用。

Culture of motor neurons from newborn rat spinal cord

SummaryA protocol for the isolation, purification and culture of motor neurons from newborn rat spinal cord was described and the effect of glial cell line-derived neurotrophic factor (GDNF) on the growth of neurite of motor neurons was investigated in vitro. Spinal motor neurons (SMNs) were dissociated from ventral spinal cord of postnatal day 1 rats. The culture system for SMNs was established by density gradient centrifugation, differential adhesion, and use of serum-free defined media and addition of exogenous GDNF. After 72-h culture, the cells displayed the characteristic morphology of motor neurons, exhibited extensive neuritic processes and were positive for choline acetyltransferase (ChAT) expression. The neurite length of SMNs in GDNF groups was significantly longer than that in control group (P<0.05). This protocol can be adapted for various postnatal motor neurons studies.A protocol for the isolation, purification and culture of motor neurons from newborn rat spinal cord was described and the effect of glial cell line-derived neurotrophic factor (GDNF) on the growth of neurite of motor neurons was investigated in vitro. Spinal motor neurons (SMNs) were dissociated from ventral spinal cord of postnatal day 1 rats. The culture system for SMNs was established by density gradient centrifugation, differential adhesion, and use of serum-free defined media and addition of exogenous GDNF. After 72-h culture, the cells displayed the characteristic morphology of motor neurons, exhibited extensive neuritic processes and were positive for choline acetyltransferase (ChAT) expression. The neurite length of SMNs in GDNF groups was significantly longer than that in control group (P<0.05). This protocol can be adapted for various postnatal motor neurons studies.

Effect of the artificial somato-autonomic neuroanastomosis on defecation after spinal cord injury and its underlying mechanisms

SummaryA new artificial somatic-autonomic neuroanastomosis has been established in male rats with spinal cord injury (SCI). Anorectal manometry and neural retrograde tracing were conducted in this animal model to analyze the mechanisms and the effects on recovery of anorectal function. The left L4 ventral root (L4VR) was intradurally micro-anastomosed to the L6 ventral root (L6VR) to establish the new regenerated neural pathway. Three months later the spinal cord was completely transected at the T9–10 level. Eight weeks later the model rats were randomly divided into two groups. The rats in the group 1 (n=8) were applied for anorectal manometry, and those in the group 2 (n=4) were used for neural retrograde tracing study with fluorogold (FG) and dextran tetramethylrhodamine (TMR). The results of anorectal manometry showed the new reflex pathway could induce rectum to contract and simultaneously electric activity of external anal sphincter (EAS) to become weak or disappearing (indicating synergetic relaxation of EAS). FG and TMR dual labeled neurons with round and elliptical shape were mainly observed in L4 angulus anterior of model rats. The regenerated neural pathways were effective to improve the rectum external sphincter synergetic status and restore the anorectal function.A new artificial somatic-autonomic neuroanastomosis has been established in male rats with spinal cord injury (SCI). Anorectal manometry and neural retrograde tracing were conducted in this animal model to analyze the mechanisms and the effects on recovery of anorectal function. The left L4 ventral root (L4VR) was intradurally micro-anastomosed to the L6 ventral root (L6VR) to establish the new regenerated neural pathway. Three months later the spinal cord was completely transected at the T9–10 level. Eight weeks later the model rats were randomly divided into two groups. The rats in the group 1 (n=8) were applied for anorectal manometry, and those in the group 2 (n=4) were used for neural retrograde tracing study with fluorogold (FG) and dextran tetramethylrhodamine (TMR). The results of anorectal manometry showed the new reflex pathway could induce rectum to contract and simultaneously electric activity of external anal sphincter (EAS) to become weak or disappearing (indicating synergetic relaxation of EAS). FG and TMR dual labeled neurons with round and elliptical shape were mainly observed in L4 angulus anterior of model rats. The regenerated neural pathways were effective to improve the rectum external sphincter synergetic status and restore the anorectal function.

Hybrid synaptogenesis formed between the somatic neurons and the automatic neurons

decrease in the exploration time of objects in a new location. Also the number of Ki67 positive cells in the 5-FU treated group was significantly lower than the control group. From these findings we conclude that 5-FU has an effect on hippocampal dependent behaviourwhich is associatedwith a reduction in cell proliferation. This animal model confirms the reports of cognitive deficits made by patients taking this drug.

Morphological changes of cholinergic nerve fibers in the urinary bladder after establishment of artificial somatic-autonomic reflex arc in rats@@@人工反射弧建立后大鼠膀胱胆碱能神经的形态学变化

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. 观察体神经, 内脏神经人工反射弧建立后?大鼠膀胱肌间神经丛分布的改变以及神经肌肉接头处的变化。 Sprague-Dawley 大鼠随机分为三组: 对照组、 脊髓横断组和手术重建组。 手术重建组大鼠术后饲养 3 个月, 与脊髓横断组大鼠一起进行脊髓横断, 再继续饲养3 个月, 对照组不做任何处理。 DiI 进行逆行神经追踪; 免疫荧光的方法显示 DiI 阳性标记细胞中的胆碱乙酰转移酶(choline acetyltransferase, ChAT); 改良的 Karnovsky-Roots法 检测膀胱铺片中神经纤维的分布。 DiI 阳性标记细胞主要分布于脊髓 L3 尾部至 L5 头侧前角, ChAT 阳性细胞和 DiI 阳性标记细胞部分重叠。 手术重建组和对照组相比, 膀胱肌间神经纤维的数量较少, 染色浓度也较浅(P < 0.05); 而手术重建组神经纤维密度较脊髓横断组增大, 染色浓度增强(P < 0.05); 且出现明显的神经再分布。 人工体内脏神经反射弧建立后, 新的传出支为体神经, 可以长入副交感神经纤维, 传出神经元的递质仍为乙酰胆碱, 膀胱内胆碱能神经纤维再生和乙酰胆碱活性增强且出现神经再分布, 这可能在膀胱的控制性排尿中起作用。