An enriched environment protects dopaminergic neurons from 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)-induced neuronal injury, but the underlying mechanism for this is not clear. Growth associated protein-43...An enriched environment protects dopaminergic neurons from 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)-induced neuronal injury, but the underlying mechanism for this is not clear. Growth associated protein-43(GAP-43) is closely associated with neurite outgrowth and axon regeneration during neural development. We speculate that an enriched environment can reduce damage to dopaminergic neurons by affecting the expression of GAP-43. This study is designed to test this hypothesis. Three-month-old female senescence-accelerated mouse prone 8(SAMP8) mice were housed for 3 months in an enriched environment or a standard environment. These mice were then subcutaneously injected in the abdomen with 14 mg/kg MPTP four times at 2-hour intervals. Morris water maze testing demonstrated that learning and memory abilities were better in the enriched environment group than in the standard environment group. Reverse-transcription polymerase chain reaction, immunohistochemistry and western blot assays showed that m RNA and protein levels of GAP-43 in the substantia nigra were higher after MPTP application in the enriched environment group compared with the standard environment group. These findings indicate that an enriched environment can increase GAP-43 expression in SAMP8 mice. The upregulation of GAP-43 may be a mechanism by which an enriched environment protects against MPTP-induced neuronal damage.展开更多
BACKGROUND: The main clinical treatments for optic nerve injury are optic canal decompression and systemic administration of hormones, but both treatments have disadvantages. OBJECTIVE: To observe the pathological c...BACKGROUND: The main clinical treatments for optic nerve injury are optic canal decompression and systemic administration of hormones, but both treatments have disadvantages. OBJECTIVE: To observe the pathological changes in the retina and growth associated protein-43 (GAP-43) expression, to compare the treatment of optic canal decompression, hormones, and their combination with the intracanalicular optic nerve injury.DESIGN, TIME AND SETTING: A randomized, controlled animal study was performed at the Department of Anatomy, Weifang Medical University, China, from September 2007 to November 2008.MATERIALS: Dexamethasone (Shandong Huaxin Pharmaceutical, China) and rabbit anti-GAP-43 polyclonal antibody (Boster, China) were used.METHODS: All 36 healthy adult rabbits were randomly assigned to control group (n = 4), simple injury group (n = 20), and treatment group (n = 12). Intracanalicular optic nerve injury models were established using the metal cylinder free-fall impact method. The control group was left intact. The treatment group (four rabbits in each subgroup) was treated by optic nerve decompression, dexamethasone treatment (1 mg/kg daily via two intravenous infusions, 1/5 total dose reduction every 3 days, for 14 days), and simultaneously giving surgery and hormone treatment.MAIN OUTCOME MEASURES: Pathological changes in the retina were determined using hematoxylin-eosin staining. GAP-43 expression was detected using immunohistochemistry in the retina.RESULTS: Retina injury induced obvious pathological changes in the retina. With prolonged time after optic nerve injury, the number of retinal ganglion cells was gradually decreased, and reached the minimum on day 14 (P〈0.01). All three treatments increased the number of retinal ganglion cells (P〈0.01), but surgery + hormone treatment was most effective. No GAP-43 cells were present in the normal retinal, but they appeared 3 days after injury, peaked 7 days after injury, and then began to decline.CONCLUSION: Intracanalicular optic nerve injury induced obvious pathological changes in the retina, including increased GAP-43 expression. Optic canal decompression and hormones improved nerve repair after injury, and their combination produced better outcomes.展开更多
BACKGROUND: Peripheral nerve injury may lead to neuropathic pain and cause a markedly increase expression of growth associated protein-43 (GAP-43) in the spinal cord and dorsal root ganglion, local anesthetics bloc...BACKGROUND: Peripheral nerve injury may lead to neuropathic pain and cause a markedly increase expression of growth associated protein-43 (GAP-43) in the spinal cord and dorsal root ganglion, local anesthetics blocking electrical impulse propagation of nerve fibers may also affect the expression of GAP-43 in the spinal cord and dorsal root ganglion. OBJECTIVE: To determine the effects of continuous peripheral nerve block by tetrodotoxin before and after nerve injury on GAP-43 expression in the dorsal root ganglion during the development of neuropathic pain. DESIGN: A randomized controlled animal experiment. SETTINGS: Department of Anesthesiology, the Second Hospital of Xiamen City; Department of Anesthesiology, the Second Affiliated Hospital of Shantou University Medical College. MATERIALS: Thirty-five Spragne Dawley (SD) rats, weighing 200 - 250 g, were randomly divided into four groups: control group (n =5), simple sciatic nerve transection group (n =10), peripheral nerve block before and after sciatic nerve transection groups (n =10). All the sciatic nerve transection groups were divided into two subgroups according to the different postoperative survival periods: 3 and 7 days (n =5) respectively. Mouse anti-GAP-43 monoclonal antibody (Sigma Co., Ltd.), supervision TM anti-mouse reagent (HRP, Changdao antibody diagnosis reagent Co., Ltd., Shanghai), and HMIAS-100 image analysis system (Qianping Image Engineering Company, Tongji Medical University) were employed in this study. METHODS: This experiment was carried out in the Department of Surgery and Pathological Laboratory, the Second Affiliated Hospital of Shantou University Medical College from April 2005 to April 2006. ①The animals were anesthetized and the right sciatic nerve was exposed and transected at 1 cm distal to sciatic notch. ② Tetrodotoxin 10 μg/kg was injected percutaneously between the greater trochanter and the posterior superior iliac spine of fight hind limb to block the sciatic nerve proximally at 1 hour before or 4 hours after nerve injury respectively, the injection was repeated in all the rats every 12 hours.③ At 3 or 7 days after nerve injury, immunohistochemistry and image analysis were used to evaluate the expression of GAP-43 in the dorsal root ganglions of L5 to the transected sciatic nerve, and quantitative analysis was also performed. ④ Statistical analysis was performed using one way analysis of variance followed by t test. MAIN OUTCOME MEASURE: Expression of GAP-43 in the fight dorsal root ganglions of L5. RESULTS: All the 35 SD rats were involved in the final analysis of results. In normal rats, there were very low expressions of GAP-43 in the dorsal root ganglions. In simple sciatic nerve transection rats 3 and 7 days after sciatic nerve transection, the average absorbance value of GAP-43 immunopositive neurons were significantly different from that in normal rats (t =8.806, 6.771, P 〈 0.01). Whereas 3 and 7 days after sciatic nerve transection in rats with peripheral nerve block before and after nerve injury, the average absorbance value of GAP-43 immunopositive neurons were not significantly different from that in normal rats (P 〉 0.05). CONCLUSION: Local anesthetic continuous peripheral nerve block before or after nerve injury can suppress nerve injury induced high expression of GAP-43 during the development of neuropathic pain.展开更多
Glial cell line-derived neurotrophic factor recombinant adenovirus vector-transfected bone marrow mesenchymal stem cells were induced to differentiate into neuron-like cells using inductive medium containing retinoic ...Glial cell line-derived neurotrophic factor recombinant adenovirus vector-transfected bone marrow mesenchymal stem cells were induced to differentiate into neuron-like cells using inductive medium containing retinoic acid and epidermal growth factor. Cell viability, micro- tubule-associated protein 2-positive cell ratio, and the expression levels of glial cell line-derived neurotrophic factor, nerve growth factor and growth-associated protein-43 protein in the su- pernatant were significantly higher in glial cell line-derived neurotrophic factor/bone marrow mesenchymal stem cells compared with empty virus plasmid-transfected bone marrow mes- enchymal stem cells. Furthermore, microtubule-associated protein 2, glial cell line-derived neurotrophic factor, nerve growth factor and growth-associated protein743 mRNA levels in cell pellets were statistically higher in glial cell line-derived neurotrophic factor/bone marrow mesen- chymal stem cells compared with empty virus plasmid-transfected bone marrow mesenchymal stem cells. These results suggest that glial cell line-derived neurotrophic factor/bone marrow mesenchymal stem cells have a higher rate of induction into neuron-like cells, and this enhanced differentiation into neuron-like cells may be associated with up-regulated expression of glial cell line-derived neurotrophic factor, nerve growth factor and growth-associated protein-43.展开更多
BACKGROUND: Ephedrine promotes neural plasticity in rats following cerebral ischemia/reperfusion injury. Ephedrine has been combined with naloxone in some studies, and it has been confirmed that their combination has...BACKGROUND: Ephedrine promotes neural plasticity in rats following cerebral ischemia/reperfusion injury. Ephedrine has been combined with naloxone in some studies, and it has been confirmed that their combination has synergistic effects on increasing neural plasticity following cerebral ischemia/reperfusion injury. OBJECTIVE: To investigate the effects of ephedrine combined with various doses of naloxone on neural plasticity and to find an optimal dose of naloxone in rats after cerebral ischemia/reperfusion injury by analyzing growth associated protein-43 (GAP-43), synaptophysin and β-endorphin expression in the hippocampal CA3 area. DESIGN, TIME AND SETTING: This immunohistochemical, randomized, controlled, animal experiment was performed at the Chongqing Research Institute of Pediatrics, China from September 2007 to June 2008. MATERIALS: Ephedrine hydrochloride injection and naloxone hydrochloride injection were respectively purchased from Shandong Lvliang Pharmaceutical Factory, China and Sichuan Jingwei Pharmaceutical Co., Ltd., China. A total of 192 healthy adult Sprague Dawley rats were used to establish models of left middle cerebral artery occlusion using the suture occlusion method. METHODS: At 2 hours following cerebral ischemia, the rats were intraperitoneally injected with 1.5 mg/kg/d ephedrine (ephedrine group), with 0.1, 0.2, or 0.3 mg/kg/d naloxone (low, moderate and high doses of naloxone groups), with 1.5 mg/kg/d ephedrine + 0.1, 0.2, or 0.3 mg/kg/d naloxone (ephedrine + low, moderate and high doses of naloxone groups), and with 0.5 mL saline (model group), respectively. MAIN OUTCOME MEASURES: GAP-43, synaptophysin and β -endorphin expression were detected in the hippocampal CA3 area using immunohistochemistry 1-4 weeks after surgery. Sensorimotor integration in rats was assessed using the beam walking test. RESULTS: GAP-43 and synaptophysin expression was greater in the ephedrine group, and in the ephedrine + moderate and high doses of naloxone groups compared with the model group. GAP-43 and synaptophysin expression was greatest in the ephedrine + high dose of naloxone group at 2 and 3 weeks alter surgery. β -endorphin expression was significantly lower in the ephedrine group, and in the ephedrine + moderate and high doses of naloxone groups compared with the model group (P 〈 0.05). β -endorphin expression was persistently low in the ephedrine + high dose of naloxone group. At 1-3 weeks after surgery, the beam walking test score was significantly higher in the ephedrine group and ephedrine + various doses of naloxone groups than in the model group (P 〈 0.05). The score was higher in the ephedrine + moderate and high doses of naloxone groups than in the ephedrine group (P 〈 0.05). Moreover, the score was increased as the dose of naloxone increased in the ephedrine + various doses of naloxone groups. CONCLUSION: Ephedrine promotes GAP-43 and synaptophysin expression, inhibits /3 -endorphin expression in the hippocampal CA3 area, and improves motor function in rats following cerebral ischemia/reperfusion injury. Naloxone does not have the above-mentioned effects. During combined treatment with ephedrine and naloxone, however, the above-described effects are enhanced with an increased dose of naloxone. The combination of ephedrine (1.5 mg/kg/d) and naloxone (0.3 mg/kg/d) can produce optimal therapeutic efficacy in treatment of cerebral ischemic injury.展开更多
[目的]观察脊髓损伤(spinal cord injury,SCI)后发生中枢性疼痛(central pain,CP)大鼠损伤远端脊髓背角中生长相关蛋白43(GAP-43)和降钙基因相关肽(CGRP)的共定位表达情况,探讨CP与CGRP阳性的初级传入神经纤维出芽再生之间的关...[目的]观察脊髓损伤(spinal cord injury,SCI)后发生中枢性疼痛(central pain,CP)大鼠损伤远端脊髓背角中生长相关蛋白43(GAP-43)和降钙基因相关肽(CGRP)的共定位表达情况,探讨CP与CGRP阳性的初级传入神经纤维出芽再生之间的关系。[方法]SD大鼠16只,随机等分为SCI组和假术(SHAM)组。SCI组大鼠用NYU撞击器损伤L1节段脊髓,撞击力为10 g×12.5 mm。SHAM组大鼠仅切除椎板,不损伤脊髓。术后每天观察双后肢自噬现象,每周测量双后肢运动功能评分(BBB scores,developed by Basso,Beattie and Bresnahan at Ohio State University)。术后4~8周每周测量后肢触压痛痛阈及冷热过敏症状,了解CP的发生情况。术后8周每组取4只行损伤远端脊髓GAP-43与CGRP免疫荧光双标记并在共聚焦显微镜下观察二者的共定位表达情况。[结果]SCI组大鼠术后均出现双后肢瘫痪及明显的CP症状,其损伤远端脊髓背角中GAP-43与CGRP的共定位表达量明显升高,分布范围明显扩大,与SHAM组比较,差异有统计学意义(P〈0.01)。[结论]CP的发生与SCI后感受伤害性刺激的CGRP阳性感觉传入纤维的出芽再生有关。展开更多
基金supported by a grant from the Health Department of Hebei Province of China,No.20120056,20140314the Funding Project for Introduced Abroad Study Personnel of Hebei Province of China,No.C2011003039
文摘An enriched environment protects dopaminergic neurons from 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)-induced neuronal injury, but the underlying mechanism for this is not clear. Growth associated protein-43(GAP-43) is closely associated with neurite outgrowth and axon regeneration during neural development. We speculate that an enriched environment can reduce damage to dopaminergic neurons by affecting the expression of GAP-43. This study is designed to test this hypothesis. Three-month-old female senescence-accelerated mouse prone 8(SAMP8) mice were housed for 3 months in an enriched environment or a standard environment. These mice were then subcutaneously injected in the abdomen with 14 mg/kg MPTP four times at 2-hour intervals. Morris water maze testing demonstrated that learning and memory abilities were better in the enriched environment group than in the standard environment group. Reverse-transcription polymerase chain reaction, immunohistochemistry and western blot assays showed that m RNA and protein levels of GAP-43 in the substantia nigra were higher after MPTP application in the enriched environment group compared with the standard environment group. These findings indicate that an enriched environment can increase GAP-43 expression in SAMP8 mice. The upregulation of GAP-43 may be a mechanism by which an enriched environment protects against MPTP-induced neuronal damage.
基金the Educational Commission of Shandong Province of China,No. J06L23
文摘BACKGROUND: The main clinical treatments for optic nerve injury are optic canal decompression and systemic administration of hormones, but both treatments have disadvantages. OBJECTIVE: To observe the pathological changes in the retina and growth associated protein-43 (GAP-43) expression, to compare the treatment of optic canal decompression, hormones, and their combination with the intracanalicular optic nerve injury.DESIGN, TIME AND SETTING: A randomized, controlled animal study was performed at the Department of Anatomy, Weifang Medical University, China, from September 2007 to November 2008.MATERIALS: Dexamethasone (Shandong Huaxin Pharmaceutical, China) and rabbit anti-GAP-43 polyclonal antibody (Boster, China) were used.METHODS: All 36 healthy adult rabbits were randomly assigned to control group (n = 4), simple injury group (n = 20), and treatment group (n = 12). Intracanalicular optic nerve injury models were established using the metal cylinder free-fall impact method. The control group was left intact. The treatment group (four rabbits in each subgroup) was treated by optic nerve decompression, dexamethasone treatment (1 mg/kg daily via two intravenous infusions, 1/5 total dose reduction every 3 days, for 14 days), and simultaneously giving surgery and hormone treatment.MAIN OUTCOME MEASURES: Pathological changes in the retina were determined using hematoxylin-eosin staining. GAP-43 expression was detected using immunohistochemistry in the retina.RESULTS: Retina injury induced obvious pathological changes in the retina. With prolonged time after optic nerve injury, the number of retinal ganglion cells was gradually decreased, and reached the minimum on day 14 (P〈0.01). All three treatments increased the number of retinal ganglion cells (P〈0.01), but surgery + hormone treatment was most effective. No GAP-43 cells were present in the normal retinal, but they appeared 3 days after injury, peaked 7 days after injury, and then began to decline.CONCLUSION: Intracanalicular optic nerve injury induced obvious pathological changes in the retina, including increased GAP-43 expression. Optic canal decompression and hormones improved nerve repair after injury, and their combination produced better outcomes.
基金the Natural Science Foundation of Guangdong Province, No.034628
文摘BACKGROUND: Peripheral nerve injury may lead to neuropathic pain and cause a markedly increase expression of growth associated protein-43 (GAP-43) in the spinal cord and dorsal root ganglion, local anesthetics blocking electrical impulse propagation of nerve fibers may also affect the expression of GAP-43 in the spinal cord and dorsal root ganglion. OBJECTIVE: To determine the effects of continuous peripheral nerve block by tetrodotoxin before and after nerve injury on GAP-43 expression in the dorsal root ganglion during the development of neuropathic pain. DESIGN: A randomized controlled animal experiment. SETTINGS: Department of Anesthesiology, the Second Hospital of Xiamen City; Department of Anesthesiology, the Second Affiliated Hospital of Shantou University Medical College. MATERIALS: Thirty-five Spragne Dawley (SD) rats, weighing 200 - 250 g, were randomly divided into four groups: control group (n =5), simple sciatic nerve transection group (n =10), peripheral nerve block before and after sciatic nerve transection groups (n =10). All the sciatic nerve transection groups were divided into two subgroups according to the different postoperative survival periods: 3 and 7 days (n =5) respectively. Mouse anti-GAP-43 monoclonal antibody (Sigma Co., Ltd.), supervision TM anti-mouse reagent (HRP, Changdao antibody diagnosis reagent Co., Ltd., Shanghai), and HMIAS-100 image analysis system (Qianping Image Engineering Company, Tongji Medical University) were employed in this study. METHODS: This experiment was carried out in the Department of Surgery and Pathological Laboratory, the Second Affiliated Hospital of Shantou University Medical College from April 2005 to April 2006. ①The animals were anesthetized and the right sciatic nerve was exposed and transected at 1 cm distal to sciatic notch. ② Tetrodotoxin 10 μg/kg was injected percutaneously between the greater trochanter and the posterior superior iliac spine of fight hind limb to block the sciatic nerve proximally at 1 hour before or 4 hours after nerve injury respectively, the injection was repeated in all the rats every 12 hours.③ At 3 or 7 days after nerve injury, immunohistochemistry and image analysis were used to evaluate the expression of GAP-43 in the dorsal root ganglions of L5 to the transected sciatic nerve, and quantitative analysis was also performed. ④ Statistical analysis was performed using one way analysis of variance followed by t test. MAIN OUTCOME MEASURE: Expression of GAP-43 in the fight dorsal root ganglions of L5. RESULTS: All the 35 SD rats were involved in the final analysis of results. In normal rats, there were very low expressions of GAP-43 in the dorsal root ganglions. In simple sciatic nerve transection rats 3 and 7 days after sciatic nerve transection, the average absorbance value of GAP-43 immunopositive neurons were significantly different from that in normal rats (t =8.806, 6.771, P 〈 0.01). Whereas 3 and 7 days after sciatic nerve transection in rats with peripheral nerve block before and after nerve injury, the average absorbance value of GAP-43 immunopositive neurons were not significantly different from that in normal rats (P 〉 0.05). CONCLUSION: Local anesthetic continuous peripheral nerve block before or after nerve injury can suppress nerve injury induced high expression of GAP-43 during the development of neuropathic pain.
文摘Glial cell line-derived neurotrophic factor recombinant adenovirus vector-transfected bone marrow mesenchymal stem cells were induced to differentiate into neuron-like cells using inductive medium containing retinoic acid and epidermal growth factor. Cell viability, micro- tubule-associated protein 2-positive cell ratio, and the expression levels of glial cell line-derived neurotrophic factor, nerve growth factor and growth-associated protein-43 protein in the su- pernatant were significantly higher in glial cell line-derived neurotrophic factor/bone marrow mesenchymal stem cells compared with empty virus plasmid-transfected bone marrow mes- enchymal stem cells. Furthermore, microtubule-associated protein 2, glial cell line-derived neurotrophic factor, nerve growth factor and growth-associated protein743 mRNA levels in cell pellets were statistically higher in glial cell line-derived neurotrophic factor/bone marrow mesen- chymal stem cells compared with empty virus plasmid-transfected bone marrow mesenchymal stem cells. These results suggest that glial cell line-derived neurotrophic factor/bone marrow mesenchymal stem cells have a higher rate of induction into neuron-like cells, and this enhanced differentiation into neuron-like cells may be associated with up-regulated expression of glial cell line-derived neurotrophic factor, nerve growth factor and growth-associated protein-43.
基金a grant from the Bureau of Health of Chongqing City, No. [2007]1(07-2-153)
文摘BACKGROUND: Ephedrine promotes neural plasticity in rats following cerebral ischemia/reperfusion injury. Ephedrine has been combined with naloxone in some studies, and it has been confirmed that their combination has synergistic effects on increasing neural plasticity following cerebral ischemia/reperfusion injury. OBJECTIVE: To investigate the effects of ephedrine combined with various doses of naloxone on neural plasticity and to find an optimal dose of naloxone in rats after cerebral ischemia/reperfusion injury by analyzing growth associated protein-43 (GAP-43), synaptophysin and β-endorphin expression in the hippocampal CA3 area. DESIGN, TIME AND SETTING: This immunohistochemical, randomized, controlled, animal experiment was performed at the Chongqing Research Institute of Pediatrics, China from September 2007 to June 2008. MATERIALS: Ephedrine hydrochloride injection and naloxone hydrochloride injection were respectively purchased from Shandong Lvliang Pharmaceutical Factory, China and Sichuan Jingwei Pharmaceutical Co., Ltd., China. A total of 192 healthy adult Sprague Dawley rats were used to establish models of left middle cerebral artery occlusion using the suture occlusion method. METHODS: At 2 hours following cerebral ischemia, the rats were intraperitoneally injected with 1.5 mg/kg/d ephedrine (ephedrine group), with 0.1, 0.2, or 0.3 mg/kg/d naloxone (low, moderate and high doses of naloxone groups), with 1.5 mg/kg/d ephedrine + 0.1, 0.2, or 0.3 mg/kg/d naloxone (ephedrine + low, moderate and high doses of naloxone groups), and with 0.5 mL saline (model group), respectively. MAIN OUTCOME MEASURES: GAP-43, synaptophysin and β -endorphin expression were detected in the hippocampal CA3 area using immunohistochemistry 1-4 weeks after surgery. Sensorimotor integration in rats was assessed using the beam walking test. RESULTS: GAP-43 and synaptophysin expression was greater in the ephedrine group, and in the ephedrine + moderate and high doses of naloxone groups compared with the model group. GAP-43 and synaptophysin expression was greatest in the ephedrine + high dose of naloxone group at 2 and 3 weeks alter surgery. β -endorphin expression was significantly lower in the ephedrine group, and in the ephedrine + moderate and high doses of naloxone groups compared with the model group (P 〈 0.05). β -endorphin expression was persistently low in the ephedrine + high dose of naloxone group. At 1-3 weeks after surgery, the beam walking test score was significantly higher in the ephedrine group and ephedrine + various doses of naloxone groups than in the model group (P 〈 0.05). The score was higher in the ephedrine + moderate and high doses of naloxone groups than in the ephedrine group (P 〈 0.05). Moreover, the score was increased as the dose of naloxone increased in the ephedrine + various doses of naloxone groups. CONCLUSION: Ephedrine promotes GAP-43 and synaptophysin expression, inhibits /3 -endorphin expression in the hippocampal CA3 area, and improves motor function in rats following cerebral ischemia/reperfusion injury. Naloxone does not have the above-mentioned effects. During combined treatment with ephedrine and naloxone, however, the above-described effects are enhanced with an increased dose of naloxone. The combination of ephedrine (1.5 mg/kg/d) and naloxone (0.3 mg/kg/d) can produce optimal therapeutic efficacy in treatment of cerebral ischemic injury.
文摘[目的]观察脊髓损伤(spinal cord injury,SCI)后发生中枢性疼痛(central pain,CP)大鼠损伤远端脊髓背角中生长相关蛋白43(GAP-43)和降钙基因相关肽(CGRP)的共定位表达情况,探讨CP与CGRP阳性的初级传入神经纤维出芽再生之间的关系。[方法]SD大鼠16只,随机等分为SCI组和假术(SHAM)组。SCI组大鼠用NYU撞击器损伤L1节段脊髓,撞击力为10 g×12.5 mm。SHAM组大鼠仅切除椎板,不损伤脊髓。术后每天观察双后肢自噬现象,每周测量双后肢运动功能评分(BBB scores,developed by Basso,Beattie and Bresnahan at Ohio State University)。术后4~8周每周测量后肢触压痛痛阈及冷热过敏症状,了解CP的发生情况。术后8周每组取4只行损伤远端脊髓GAP-43与CGRP免疫荧光双标记并在共聚焦显微镜下观察二者的共定位表达情况。[结果]SCI组大鼠术后均出现双后肢瘫痪及明显的CP症状,其损伤远端脊髓背角中GAP-43与CGRP的共定位表达量明显升高,分布范围明显扩大,与SHAM组比较,差异有统计学意义(P〈0.01)。[结论]CP的发生与SCI后感受伤害性刺激的CGRP阳性感觉传入纤维的出芽再生有关。