Evaluation of the excopula ejaculatory potentials of Bersama engleriana in spinal male rats

The aim of this study was to investigate the effects of Bersama engleriana and its potential mechanism on fictive ejaculation in spinal male rats. The electromyographic activities of the bulbospongiosus muscles were recorded in spinal cord transected and urethane-anesthetized rats treated intravenously with aqueous （100 mg kg^-1） and methanolic （100 mg kg^-1） extracts from the dried leaves of B. engleriana in the absence and presence of dopamine （0.1 μmol kg^-1） or oxytocin （0.5 UI kg^-1）. Mechanical stimulations of the urethra were also carried out 5 min after the sequential treatments. A single intravenous administration of aqueous （100 mg kg^-1） and methanolic （100 mg kg^-1） extracts of B. engleriana did not activate fictive ejaculation. The electromyography recorded after the application of the plant extract was similar to that obtained after intravenous saline injection （200 Gl min^-1） with no contraction of the bulbospongiosus muscles. Dopamine （0.1 μmol kg^-1） and oxytocin （0.5 UI kg^-1） induced rapid rhythmic contractions （P 〈 0.001） of the bulbospongiosus muscles accompanied by penile erection and sometimes with expulsion of the seminal plugs. Pretreatment of rats with the two plant extracts completely abolished the occurrence of ejaculation induced by dopamine （0.1 μmol kg^-1） and oxytocin （0.5 UI kg^-1）. Mechanical stimulation of the urethra carried out 5 min after the sequential treatments always induced penile movements and erections. The inhibitory effect of B. engleriana extracts on the expression offictive ejaculation in spinal male rat is mediated through dopaminergic and oxytocinergic pathways. This prolonged ejaculatory latency caused by B. engleriana could support its potential use in patients with rapid ejaculation.

Changes in Synapses and Axons Demonstrated by Synaptophysin Immunohistochemistry Following Spinal Cord Compression Trauma in the Rat and Mouse

Objective and methods To evaluate synaptic changes using synaptophysin immunohistochemstry in rat and mouse, which spinal cords were subjected to graded compression trauma at the level of Th8-9. Results Normal animals showed numerous fine dots of synaptophysin immunoreactivity in the gray matter. An increase in synaptophysin immunoreactivity was observed in the neuropil and synapses at the surface of motor neurons of the anterior horns in the ThS-9 segments lost immunoreactivity at 4-hour point after trauma. The immunoreactive synapses reappeared around motor neurons at 9-day point. Unexpected accumulation of synaptophysin immunoreactivity occurred in injured axons of the white matter of the compressed spinal cord. Conclusion Synaptic changes were important components of secondary injuries in spinal cord trauma. Loss of synapses on motor neurons may be one of the factors causing motor dysfunction of hind limbs and formation of new synapses may play an import,ant role in recovery of motor function. Synaptophysin immunohistochemistry is also a good tool for studies of axonal swellings in spinal cord injuries.

Effects of Epidural Spinal Cord Stimulation and Treadmill Training on Locomotion Function and Ultrastructure of Spinal Cord Anterior Horn after Moderate Spinal Cord Injury in Rats

Objective:To investigate the effects of epidural spinal cord stimulation(ESCS) and treadmill training on the locomotion function and ultrastructure of spinal cord anterior horn after moderate spinal cord injury in rats.Method:Nine adult female Sprague-Dawley rats were randomly distributed into three groups:①spinal cord injury group(SI,n=3).②spinal cord injury plus ESCS group(SE,n=3).③spinal cord injury plus treadmill training group(TT,n=3).All rats received a moderate spinal cord injury surgery.Four weeks after surgery,rats in SE group received an electrode implantation procedure,with the electrode field covering spinal cord segments L2-S1.Four weeks after electrode implantation,rats received subthreshold ESCS for 30 min/d.Rats in TT group received 4cm/s treadmill training for 30min/d.Rats in SI group received no intervention,as a control group.All procedures in these three groups lasted four weeks.The open field Basso,Beattie and Bresnahan(BBB) scale was used before and after intervention to evaluate rats' hindlimb motor function.Result:After four weeks intervention,rats in TT group improved their open field locomotion scores to 20.In contrast,no significant improvement was observed in groups SI and SE.The morphology of synapses and neurons were similar regardless of whether rats had undergone ESCS,treadmill training or not.Conclusion:ESCS alone was not sufficient to improve the walking ability of spinal cord injured rats.ESCS or treadmill training alone might not contribute to the changes of ultrastructure in anterior horn of spinal cord that underlie the recovery of walking ability.Further research is needed to understand the contributions of combination of ESCS and treadmill training to the rehabilitation of spinal cord injured rats.

APOPTOSIS AFTER SPINAL CORD INJURY IN RATS

Objective To confirm the role played by apoptosis in spinal cord injury. Methods 36 rats models of spinal cord injury were made by Allen method. Histological examinations using HE staining and in situ end-labeling were used to observe apoptosis in spinal cord tissues from 1h to 21d after injury. Results HE staining sections showed hemorrhage and necrosis, neuronal degeneration and glial cell proliferation. In situ end-labeling sections showed the appearance of apoptosis in both gray and white matter as well as in both central and surrounding region. The number of apoptotic cells increased from l2h after injury, increased to the peak at 4d and declined to normal at 21d. Conclusion The results suggest that apoptosis, especially glial apoptosis, plays a role in the pathogenesis of spinal cord injury.

Changes in neurological and pathological outcomes in a modified rat spinal cord injury model with closed canal

Most animal spinal cord injury models involve a laminectomy,such as the weight drop model or the transection model.However,in clinical practice,many patients undergo spinal cord injury while maintaining a relatively complete spinal canal.Thus,open spinal cord injury models often do not simulate real injuries,and few previous studies have investigated whether having a closed spinal canal after a primary spinal cord injury may influence secondary processes.Therefore,we aimed to assess the differences in neurological dysfunction and pathological changes between rat spinal cord injury models with closed and open spinal canals.Sprague-Dawley rats were randomly divided into three groups.In the sham group,the tunnel was expanded only,without inserting a screw into the spinal canal.In the spinal cord injury with open canal group,a screw was inserted into the spinal canal to cause spinal cord injury for 5 minutes,and then the screw was pulled out,leaving a hole in the vertebral plate.In the spinal cord injury with closed canal group,after inserting a screw into the spinal canal for 5 minutes,the screw was pulled out by approximately 1.5 mm and the flat end of the screw remained in the hole in the vertebral plate so that the spinal canal remained closed;this group was the modified model,which used a screw both to compress the spinal cord and to seal the spinal canal.At 7 days post-operation,the Basso-Beattie-Bresnahan scale was used to measure changes in neurological outcomes.Hematoxylin-eosin staining was used to assess histopathology.To evaluate the degree of local secondary hypoxia,immunohistochemical staining and western blot assays were applied to detect the expression of hypoxia-inducible factor 1α(HIF-1α)and vascular endothelial growth factor(VEGF).Compared with the spinal cord injury with open canal group,in the closed canal group the Basso-Beattie-Bresnahan scores were lower,cell morphology was more irregular,the percentage of morphologically normal neurons was lower,the percentages of HIF-1α-and VEGF-immunoreactive cells were higher,and HIF-1αand VEGF protein expression was also higher.In conclusion,we successfully established a rat spinal cord injury model with closed canal.This model could result in more serious neurological dysfunction and histopathological changes than in open canal models.All experimental procedures were approved by the Institutional Animal Care Committee of Shanghai Ninth People’s Hospital,Shanghai Jiao Tong University School of Medicine,China(approval No.HKDL201810)on January 30,2018.

Culture of Motor Neurons from Newborn Rat Spinal Cord

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 acetyl- transferase （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.

Neurological recovery and antioxidant effects of resveratrol in rats with spinal cord injury: a meta-analysis

Objective:To critically assess the neurological recovery and antioxidant effects of resveratrol in rat models of spinal cord injury.Data sources:Using“spinal cord injury”,“resveratrol”and“animal experiment”as the main search terms,all studies on the treatment of spinal cord injury in rats by resveratrol were searched for in PubMed,EMBASE,MEDLINE,Web of Science,Science Direct,China National Knowledge Infrastructure,Wanfang,VIP,and SinoMed databases by computer.The search was conducted from their inception date to April 2017.No language restriction was used in the literature search.Data selection:The methodological quality of each study was assessed by the initial Stroke Therapy Academic Industry Roundtable recommendations.Two reviewers independently selected studies according to the title,abstract and full text.The risk of bias in the included studies was also evaluated.Meta-analyses were performed with Review Manager 5.3 software.Outcome measures:Neurological function was assessed by the Basso,Beattie,and Bresnahan scale score,inclined plane score and Gale’s motor function score.Molecular-biological analysis of antioxidative effects was conducted to determine superoxide dismutase levels,malondialdehyde levels,nitric oxide synthase activity,nitric oxide levels,xanthine oxidase and glutathione levels in spinal cord tissues.Results:The methodological quality of the 12 included studies was poor.The results of meta-analysis showed that compared with the control group,resveratrol significantly increased the Basso,Beattie,and Bresnahan scale scores after spinal cord injury(n=300,mean difference(MD)=3.85,95%confidence interval(CI)[2.10,5.59],P<0.0001).Compared with the control group,superoxide dismutase levels were significantly elevated(n=138,standardized mean difference(SMD)=5.22,95%CI[2.98,7.45],P<0.00001),but malondialdehyde levels were significantly diminished(n=84,SMD=–3.64,95%CI[–5.84,–1.43],P=0.001)in the spinal cord of the resveratrol treatment group.Conclusions:Resveratrol promoted neurological recovery and exerted antioxidative effects in rat models of spinal cord injury.The limited quality of the included studies reduces the application of this meta-analysis.Therefore,more high-quality studies are needed to provide more rigorous and objective evidence for the pre-clinical treatment of spinal cord injury.

A comprehensive study of long-term skeletal changes after spinal cord injury in adult rats

Spinal cord injury（SCI）-induced bone loss represents the most severe osteoporosis with no effective treatment.Past animal studies have focused primarily on long bones at the acute stage using adolescent rodents. To mimic chronic SCI in human patients, we performed a comprehensive analysis of long-term structural and mechanical changes in axial and appendicular bones in adult rats after SCI. In this experiment, 4-month-old Fischer 344 male rats received a clinically relevant T13 contusion injury. Sixteen weeks later, sublesional femurs, tibiae,and L4 vertebrae, supralesional humeri, and blood were collected from these rats and additional non-surgery rats for micro-computed tomography（m CT）, micro-finite element, histology, and serum biochemical analyses.At trabecular sites, extreme losses of bone structure and mechanical competence were detected in the metaphysis of sublesional long bones after SCI, while the subchondral part of the same bones showed much milder damage. Marked reductions in bone mass and strength were also observed in sublesional L4 vertebrae but not in supralesional humeri. At cortical sites, SCI induced structural and strength damage in both sub- and supralesional long bones. These changes were accompanied by diminished osteoblast number and activity and increased osteoclast number and activity. Taken together, our study revealed site-specific effects of SCI on bone and demonstrated sustained inhibition of bone formation and elevation of bone resorption at the chronic stage of SCI.

Effects of brain-derived neurotrophic factor on synapsin expression in rat spinal cord anterior horn neurons cultured in vitro

Brain-derived neurotrophic factor （BDNF） promotes synaptic formation and functional maturation by upregulating synapsin expression in cortical and hippocampal neurons. However, it remains controversial whether BDNF affects synapsin expression in spinal cord anterior horn neurons. Wistar rat spinal cord anterior horn neurons were cultured in serum-supplemented medium containing BDNF, BDNF antibody, and Hank＇s solution for 3 days, and then synapsin I and synaptophysin protein and mRNA expression was detected. Under serum-supplemented conditions the number of surviving neurons in the spinal cord anterior horn was similar among BDNF, anti-BDNF, and control groups （P 〉 0.05）. Synapsin I and synaptophysin protein and mRNA expressions were increased in BDNF-treated neurons, but decreased in BDNF antibody-treated neurons （P 〈 0.01）. These results indicated that BDNF significantly promotes synapsin I and synaptophysin expression in in vitro-cultured rat spinal cord anterior horn neurons.

Cellular apoptosis and Caspase-12 expression in a rat model of progressive spinal cord compression

BACKGROUND： Studies have demonstrated that the mechanisms underlying cellular apoptosis signal transduction focus on two pathways： intracellular mitochondria and extracellular death receptor. The current evidence supports that signal transduction of cellular apoptosis also includes endoplasmic reticulum stress signal transduction. OBJECTIVE： To observe Caspase-12 expression and cellular apoptosis following ischemia in rats with progressive spinal cord compression, and to verify the influence of endoplasmic reticulum stress on the apoptosis induced by spinal cord injury. DESIGN, TIME AND SETTING： A randomized, controlled, animal trial was performed at the Institute of Neuroscience in Chongqing Medical University between January and October in 2006. MATERIALS： Immunohistochemical kit, diaminobenzidine, and TUNEL kit were purchased from Beijing Zhongshan Biotechnology, China; rabbit anti-rat Caspase-12 monoclonal antibody was provided by Santa Cruz, USA. METHODS： Sixty Wistar rats, aged 3-4 months, were randomly assigned to a model group （n = 50）, which underwent spinal cord compression in the L1 segment following L1 laminectomy and articular process excision to establish a model of progressive spinal cord compression, and a sham-surgery group （n = 10）, which underwent only laminectomy. Starting with the first day after surgery, the rats were locally anesthetized, the skin was opened, and the screw was rotated by 1/4 of a cycle, twice weekly. MAIN OUTCOME MEASURES： At 3, 7, 14, 21, and 28 days after surgery, rats from each group were anesthetized, and the spinal cords were resected. Pathological changes following spinal cord compression were determined using hematoxylin-eosin staining, Nissl dye, and transmission electron microscopy. The TUNEL method was used to observe neuronal apoptosis in the compressed spinal cord segments. Immunohistochemistry and Western blot were utilized to detect Caspase-12 expression in the compressed segments. RESULTS： Cellular swelling, neural degeneration, and altered endoplasmic reticulum structures were observed at 3 days following compression. Symptoms became gradually aggravated with increasing compression time. Compared with the sham-surgery group, the number of apoptotic neurons was remarkably increased in compressed segments of the model group （P 〈 0.05）, and Caspase-12 expression was also shown to increase （P 〈 0.05）. CONCLUSION： Neuronal apoptosis was a predominant pathological factor resulting in secondary spinal cord injury during progressive spinal cord compression, and Caspase-12 was shown to be possibly involved in neuronal apoptosis induced by progressive spinal cord compression.

The effect of microgene pSVPoMcat to modify Schwann cell on GAP -43 expression after spinal cord injury in adult rats

Objective To study the effect of microgene pSVP oMcat implanted to modify schwann cell on growth associated protein -43(GAP -43)expression after spinal cord injury in adult rats.Method Hemisected of the T8segment of the sp inal cord was performed for all the experiment rats.The rats were randomly divided into three groups as follows:Group Awith microgene pSVPoMca t implanted to genetically modify SC;Group B with SC implanted ;Group C with hemisection of the spinal cord o nly.The changes of expression of GAP-43in spinal cord were observed by immunochemistry with antibodies against GAP -43.Simultaneous,the combined behavioral scores(CBS)was measured.Result There were not any different (P >0.05)among the three groups in first week a nd 12week.There were significant di ffeence(P <0.05)among three groups in 2nd,8th,and more dxpression of GAP -43at the 2nd week in gr oup A.The neurofunctional recovery was best in group A.Conclusion The microgene pSVPoMcat implanted t o modify schwann cell can promote the expression of GAP -43in spinal cord a nd func-tional recovery in adults rats after SCI.

Research progress in three-dimensional reconstruction of the rat spinal tract

BACKGROUND： Recently, three-dimensional （3D） reconstruction of the corticospinal tract has been attempted in treatment for corticospinal tract injury. However, results remain unsatisfactory. OBJECTIVE： This manuscript reviews technique progress and problems in 3D reconstruction of rat spinal tracts, as well as 3D reconstruction of human spinal tracts. RETRIEVAL STRATEGY： Using the keywords ＂rat, spinal tracts, three-dimensional reconstruction＂, the PubMed database was searched for English articles pertaining to 3D reconstruction of the rat spinal tract that were published between January 1996 and January 2007. Meanwhile, the above-mentioned keywords in Chinese were also used to search the CNK1 database for articles that were published between January 1999 and January 2007. Inclusion criteria： manuscripts that addressed the study of 3D reconstruction of the rat spinal tract and review articles. Exclusion criteria： old and repetitive articles. All manuscripts were initially evaluated, followed by extensive review. LITERATURE EVALUATION： A total of 154 related manuscripts were collected; a total of 27 were evaluated and reviewed for the present review. One manuscript assessed rat behavioral functions, four were experimental reports addressing micro-3D reconstruction techniques, ten were experiment reports about image analysis of rat corticospinal tracts, and twelve were experiment articles related to image processing of serial spinal cord sections. DATA SYNTHESIS： Rat spinal cord sections were obtained through section staining or magnetic resonance imaging （MRI） techniques, specifically localizing the inner tracts. Software was used to construct 3D reconstruction from the serial sections to observe and analyze rat spinal cord structures. The rat spinal cord is small, with complicated inner tracts, which makes accurate 3D reconstruction difficult. CONCLUSION： The assembly of 3D reconstructions from rat spinal cord serial sections and the visualization of the inner tracts are imperative for studying rat spinal cord diseases.

Inhibition of ciliary neurotrophic factor in a rat model of transected spinal cord

Ciliary neurotrophic factor （CNTF） dramatically increases following spinal cord injury and participates in the repair process, although some studies have shown that CNTF plays a role in promoting glial scar formation following spinal cord injury. The antibody closure model can be used to inhibit CNTF expression following spinal cord injury, thereby furthering the understanding of the role of CNTF in spinal cord injury repair. In the present experiment, spinal catheters were placed in the vertebral canal of spinal cord transected rats, and CNTF antibodies were injected following fixation of the paraspinal muscle catheter. At 24 hours after a single CNTF antibody injection, CNTF expression decreased in the thoracic and lumbar spinal cord and recovered to normal levels by 48 72 hours. CNTF antibody treatment can effectively block endogenous CNTF expression in the thoracic and lumbar spinal cord during an interval of less than 24 hours in transected rats.

Effect of electro-acupuncture on the expression of heat shock protein-70 gene in rat spinal cords following spinal cord injury

BACKGROUND： It is generally believed that the mechanism by which heat shock protein-70 （HSP70） protects cells is related to its effectiveness in maintaining the normal stereochemical structure of intracellular proteins, and in participating in the process of cell apoptosis. Whether electro-acupuncture participates in HSP70 expression and produces neuroprotective effects remain unclear. OBJECTIVE： This study aimed at detecting HSP70 expression after electro-acupuncture in rats with transected spinal cord, in order to further validate the mechanism of electro-acupuncture-induced effects in the treatment of spinal cord injury. DESIGN： A controlled observational experiment. SETTING： Shanghai University of Traditional Chinese Medicine and Toho University, School of Medicine. MATERIALS： Seventy adult male Sprague-Dawley rats of SPF grade, weighing 200± 20 g, were provided by the Laboratory Animal Center of Shanghai University of Traditional Chinese Medicine, with permission No. SYXK （hu） 2004 - 2005. The animals were handled in accordance with the requests from Animal Ethics Committees for guidance. A G6805-2 multiple purpose treatment machine was used （Shanghai Medical Instruments High-Tech Co.,Ltd., Shanghai, China）. METHODS： This study was carried out in the state level laboratories of Shanghai University of Traditional Chinese Medicine and Toho University, School of Medicine between January 2005 and July 2007. The rats were randomly divided into the electro-acupuncture treated group, which received electro-acupuncture treatment in addition to spinal cord surgery and the control group, which received only spinal cord surgery, with 35 rats in each group. All the rats underwent the same surgery consisting of spinal cord transection at the T10 level. If the spinal cord was completely transected and the two posterior limbs were completely paralyzed, then the surgery was considered successful and the animal was kept for further analysis and testing. After surgery, rats in the experimental group were electro-acupunctured with a G6805-2 multiple purpose treatment machine. Two needle electrodes were inserted under the T7 and T10 spinal processes, The treatment was administered once a day for 20 minutes. Rats in the control group were not given any treatment after surgery. Five rats were sacrificed separately in each group on days 1, 2, 3, 7, 14, 21 and 28 after surgery. HSP70 gene expression at the site of lesion was located and quantitatively analyzed by immunohistochemistry and real-time PCR methods. Simultaneously, the spinal cord injury region and neurons were observed by HE and Klüver-Barrera stainings. MAIN OUTCOME MEASURES： （1）HSP70 gene expression in the spinal cord injury region. （2） The number of neurons in the spinal cord injury region. RESULTS： Seventy rats were involved in the final analysis. （1）At the end of each pre-determined block of time, HSP70 mRNA level in the spinal cord injury region of rats in the electro-acupuncture treated group was significantly higher than that in the control group （P 〈 0.05）. HSP70 gene expression in the two groups reached peak levels on day 2 after surgery. （2） On days 7, 14, 21 and 28 after surgery, the number of neurons in the spinal cord injury region in the electro-acupuncture treated group was significantly higher than that in the control group （P 〈 0.05）. CONCLUSION： Electro-acupuncture can effectively enhance HSP70 expression in the spinal cord injury region. HSP70 may participate in this apparent neuroprotective effect.

Expression of PirB in Normal and Injured Spinal Cord of Rats

The expression of paired immunoglobulin-like receptor B (PirB) in normal and injured spinal cord of rats was investigated. The SD rat hemi-sectioned spinal cord injury (SCI) model was established. Before and 1, 3, 7, 10 days after SCI, the spinal cord tissues were harvested, and Western blot and immunohistochemistry were used to examine the expression and location of PirB. The results showed that the expression level of PirB in the normal spinal cord of SD rats was low. At the first day after SCI, the expression of PirB was obviously increased, and that in the injured spinal cord from the first day to the 10th day was significantly higher than in the normal spinal cord. The positive expression of PirB in neurons from different regions of gray matter of the injured spinal cord was seen. It was concluded that the expression of PirB in the normal spinal cord of rats was low. The expression of PirB in SCI was significantly increased till at least the 10th day.

Effects of neural stem cell transplantation on the motor function of rats with contusion spinal cord injuries:a meta-analysis

Objective:To judge the efficacies of neural stem cell(NSC)transplantation on functional recovery following contusion spinal cord injuries(SCIs).Data sources:Studies in which NSCs were transplanted into a clinically relevant,standardized rat model of contusion SCI were identified by searching the PubMed,Embase and Cochrane databases,and the extracted data were analyzed by Stata 14.0.Data selection:Inclusion criteria were that NSCs were used in in vivo animal studies to treat contusion SCIs and that behavioral assessment of locomotor functional recovery was performed using the Basso,Beattie,and Bresnahan lo-comotor rating scale.Exclusion criteria included a follow-up of less than 4 weeks and the lack of control groups.Outcome measures:The restoration of motor function was assessed by the Basso,Beattie,and Bresnahan locomotor rating scale.Results:We identified 1756 non-duplicated papers by searching the aforementioned electronic databases,and 30 full-text articles met the inclusion criteria.A total of 37 studies reported in the 30 articles were included in the meta-analysis.The meta-analysis results showed that transplanted NSCs could improve the motor function recovery of rats following contusion SCIs,to a moderate extent(pooled standardized mean difference(SMD)=0.73;95%confidence interval(CI):0.47–1.00;P<0.001).NSCs obtained from different donor species(rat:SMD=0.74;95%CI:0.36–1.13;human:SMD=0.78;95%CI:0.31–1.25),at different donor ages(fetal:SMD=0.67;95%CI:0.43–0.92;adult:SMD=0.86;95%CI:0.50–1.22)and from different origins(brain-derived:SMD=0.59;95%CI:0.27–0.91;spinal cord-derived:SMD=0.51;95%CI:0.22–0.79)had similar efficacies on improved functional recovery;however,adult induced pluripotent stem cell-derived NSCs showed no significant efficacies.Furthermore,the use of higher doses of transplanted NSCs or the administration of immunosuppressive agents did not promote better locomotor function recovery(SMD=0.45;95%CI:0.21–0.70).However,shorter periods between the contusion induction and the NSC transplantation showed slightly higher efficacies(acute:SMD=1.22;95%CI:0.81–1.63;subacute:SMD=0.75;95%CI:0.42–1.09).For chronic injuries,NSC implantation did not significantly improve functional recovery(SMD=0.25;95%CI:–0.16 to 0.65).Conclusion:NSC transplantation alone appears to be a positive yet limited method for the treatment of contusion SCIs.

Alteration of Nitric Oxide Synthase in Experimental Spinal Cord Injury in Rats

In order to detect the role of NO to the secondary damage following spinal cord injury (SCI). NOS in the injury site (T\-8) were studied using a rat SCI model induced by Allens weight drop method (10 g2.5 cm). The results suggested that activities of NOS significantly increased in 10 min\, 1\,2\,4\,8 h. The results indicated that NO was related to SCI. The rise of NO following SCI might lead to secondary spinal cord damage.\;

Role of NO in the inhibition of formalin-induced hyperalgesia after intraspinal injection of ACTH in rats

Objective: To study the role of nitric oxide (NO) in the inhibition of formalin-induced hyperalgesia aller intraspinal injection of adrenocorticotropic hormone (ATCH) in rats. Methods: NADPH-d histochemistry assay of the spinal cord, immuno-histochemical staining of c-fos protein (fos) and determination of the content of gama-aminobutyric acid (CABA) of ’ the spinal spinal cord tissue were performed Results: lntraspinal injection,of ACTH significantly inhibited the increase of nitrie oxide synthetase (NOS)positive . neurons, fos-positive neurons and the elevation of GABA level in the lumbar seg ment of the spinal cord which could be partially reversed with the adminnistration of 10 μmol L-arginine (Arg)Conclu- sion:The decrease of NO synthesis might play a part in the inhibition of formalin -induced hyperalgesia after intraspinal injec- tion of ACTH

Protective effect of sodium valproate on motor neurons in the spinal cord following sciatic nerve injury in rats

BACKGROUND: Sodium valproate (VPA) is used to be an effective anti-epileptic drug. VPA possesses the characteristics of penetrating rapidly through the blood-brain barrier (BBB) and increasing levels of Bcl-2 and growth cone-associated protein (GAP) 43 in spinal cord. OBJECTIVE: To observe the effect of VPA on Bcl-2 expression and motor neuronal apoptosis in spinal cord of rats following sciatic nerve transection. DESIGN: Randomized controlled experiment. SETTING: Department of Hand Surgery and Microsurgery, Wuhan Puai Hospital. MATERIALS: A total of 30 male healthy SD rats of clean grade and with the body mass of 180-220 g were provided by Experimental Animal Center of Medical College of Wuhan University. Sodium Valproate Tablets were purchases from Hengrui Pharmaceutical Factory, Jiangsu. METHODS: The experiment was performed in the Central Laboratory of Wuhan Puai Hospital and Medical College of Wuhan University from February to May 2006. Totally 30 rats were randomly divided into two groups: treatment group (n =15) and model group (n =15). Longitudinal incision along backside of right hind limbs of rats was made to expose sciatic nerves, which were sharply transected 1 cm distal to the inferior margin of piriform muscle after nerve liberation under operation microscope to establish sciatic nerve injury rat models. Sodium Valproate Tablets were pulverized and diluted into 50 g/L suspension with saline. On the day of operation, the rats in the treatment group received 6 mL/kg VPA suspension by gastric perfusion, once a day, whereas model group received 10 mL/kg saline by gastric perfusion, once a day. L4-6 spinal cords were obtained at days 1, 4, 7, 14 and 28 after operation, respectively. Terminal deoxyribonucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling (TUNEL) technique and immunohistochemical method (SP method) were used to detect absorbance (A) of neurons with positive Bcl-2 expression. Apoptotic rate of cells (number of apoptotic cells/total number of cells×100%) was calculated. MAIN OUTCOME MEASURES: A value of neurons with positive Bcl-2 expression and apoptotic rate in spinal cord of rats in the two groups. RESULTS: A total of 30 SD rats were involved in the result analysis. ①expression of positive Bcl-2 neurons: A value of positive Bcl-2 neurons were 0.71±0.02, 0.86±0.04, 1.02±0.06 at days 4, 7 and 14, respectively after operation in the treatment group, which were obviously higher than those in the model group (0.62±0.03, 0.71±0.05, 0.89±0.04, t = 3.10-4.50, P < 0.05). ②apoptotic result of motor neurons: Apoptotic rate of motor neurons in spinal cord was (6.91±0.89)% and (15.12±2.34)% at days 7 and 14 in the treatment group, which was significantly lower than those in the model group [(9.45±1.61)%, (19.35±0.92)%, t = 2.39, 3.03. P < 0.05]. CONCLUSION: VPA can increase expression of Bcl-2 in spinal cord and reduce neuronal apoptosis in rats following sciatic nerve injury, and has protective effect on motor neuron in spinal cord of rats.

Tail nerve electrical stimulation-induced walking training promotes restoration of locomotion and electrophysiology in rats with chronic spinal cord injury

Functional recovery is the final goal in the treatment of spinal cord injury. However, to date, few treatment strategies have demonstrated significant locomotor improvement in animal experiments. By using tail nerve electrical stimulation (TANES) as an open-field locomotor training method combined with glial scar ablation and cell transplantation, we have successfully promoted locomotor recovery in rats with chronic spinal cord contusion injury. The purpose of the present study is to further investigate the mechanism of TANES and its effect on electrophysiology. Spinal cord segment T10 of female, adult Long-Evans rats was contused using the NYU impactor device with 25 mm height setting. After injury, rats were randomly divided into three groups. Group I was used as a control without any treatment, group II and group III were subjected to basic treatment including glial scar ablation and transplantation of olfactory lamina propria 6 weeks after injury, and group III received TANES-induced open-field locomotor training weekly after basic treatment. All animals were allowed to survive 22 weeks, except some rats which were transected. Basso, Beattie, and Bresnahan (BBB) open-field locomotor rating scale, horizontal ladder rung walking test, and electrophysiological tests were used to assess the restoration of functional behavior and conduction. Results showed that TANES significantly improves locomotor recovery and spinal cord conduction, reflex, as well as significantly reduces the occurrence of autophagia. Additionally, after transection, trained rats still maintained higher BBB score than that of control rats. This may be related to the activity-dependent plasticity promoted by TANES-induced locomotor training.