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Sample records for acute sciatic nerve

  1. Swimming exercise in the acute or late phase after sciatic nerve crush accelerates nerve regeneration.

    PubMed

    Teodori, Rosana Macher; Betini, Joice; de Oliveira, Larissa Salgado; Sobral, Luciane Lobato; Takeda, Sibele Yoko Mattozo; de Lima Montebelo, Maria Imaculada

    2011-01-01

    There is no consensus about the best time to start exercise after peripheral nerve injury. We evaluated the morphological and functional characteristics of the sciatic nerves of rats that began to swim immediately after crush nerve injury (CS1), those that began to swim 14 days after injury (CS14), injured rats not submitted to swimming (C), and uninjured rats submitted to swimming (S). After 30 days the number of axons in CS1 and CS14 was lower than in C (P < 0.01). The diameter of axons and nerve fibers was larger in CS1 (P < 0.01) and CS14 (P < 0.05) than in C, and myelin sheath thickness was lower in all crushed groups (P < 0.05). There was no functional difference between CS1 and CS14 (P > 0.05). Swimming exercise applied during the acute or late phase of nerve injury accelerated nerve regeneration and synaptic elimination after axonotmesis, suggesting that exercise may be initiated immediately after injury.

  2. Swimming Exercise in the Acute or Late Phase after Sciatic Nerve Crush Accelerates Nerve Regeneration

    PubMed Central

    Teodori, Rosana Macher; Betini, Joice; de Oliveira, Larissa Salgado; Sobral, Luciane Lobato; Takeda, Sibele Yoko Mattozo; Montebelo, Maria Imaculada de Lima

    2011-01-01

    There is no consensus about the best time to start exercise after peripheral nerve injury. We evaluated the morphological and functional characteristics of the sciatic nerves of rats that began to swim immediately after crush nerve injury (CS1), those that began to swim 14 days after injury (CS14), injured rats not submitted to swimming (C), and uninjured rats submitted to swimming (S). After 30 days the number of axons in CS1 and CS14 was lower than in C (P < 0.01). The diameter of axons and nerve fibers was larger in CS1 (P < 0.01) and CS14 (P < 0.05) than in C, and myelin sheath thickness was lower in all crushed groups (P < 0.05). There was no functional difference between CS1 and CS14 (P > 0.05). Swimming exercise applied during the acute or late phase of nerve injury accelerated nerve regeneration and synaptic elimination after axonotmesis, suggesting that exercise may be initiated immediately after injury. PMID:21876821

  3. [Sciatic nerve intraneural perineurioma].

    PubMed

    Bonhomme, Benjamin; Poussange, Nicolas; Le Collen, Philippe; Fabre, Thierry; Vital, Anne; Lepreux, Sébastien

    2015-12-01

    Intraneural perineurioma is a benign tumor developed from the perineurium and responsible for localized nerve hypertrophy. This uncommon tumor is characterized by a proliferation of perineural cells with a "pseudo-onion bulb" pattern. We report a sciatic nerve intraneural perineurioma in a 39-year-old patient. PMID:26586011

  4. Femoral and sciatic nerve block for knee arthroscopy in a patient with acute intermittent porphyria.

    PubMed

    Bosch, L; Villar, T; Latorre, M Y; Pacreu, S

    2016-01-01

    Acute intermittent porphyria is an autosomal dominant disorder that results from a partial deficiency of porphobilinogen deaminase and that causes very severe symptoms. Attacks may be triggered by a series of drugs and by other factors that the anesthesiologist should be aware of in order to reduce morbidity and mortality. Our objective is to review anesthetic considerations in acute intermittent porphyria. We present the case of a patient diagnosed with acute intermittent porphyria who was scheduled for knee arthroscopy. The anesthetic technique used was a femoral and sciatic nerve block under sedation with an infusion of remifentanil. The surgery proceeded without incident and the patient was discharged home after 24h. We consider the use of a peripheral plexus block of the lower limb to have been the safest anesthetic technique for this patient. PMID:27220836

  5. Long-Standing Motor and Sensory Recovery following Acute Fibrin Sealant Based Neonatal Sciatic Nerve Repair.

    PubMed

    Perussi Biscola, Natalia; Politti Cartarozzi, Luciana; Ferreira Junior, Rui Seabra; Barraviera, Benedito; Leite Rodrigues de Oliveira, Alexandre

    2016-01-01

    Brachial plexus lesion results in loss of motor and sensory function, being more harmful in the neonate. Therefore, this study evaluated neuroprotection and regeneration after neonatal peripheral nerve coaptation with fibrin sealant. Thus, P2 neonatal Lewis rats were divided into three groups: AX: sciatic nerve axotomy (SNA) without treatment; AX+FS: SNA followed by end-to-end coaptation with fibrin sealant derived from snake venom; AX+CFS: SNA followed by end-to-end coaptation with commercial fibrin sealant. Results were analyzed 4, 8, and 12 weeks after lesion. Astrogliosis, microglial reaction, and synapse preservation were evaluated by immunohistochemistry. Neuronal survival, axonal regeneration, and ultrastructural changes at ventral spinal cord were also investigated. Sensory-motor recovery was behaviorally studied. Coaptation preserved synaptic covering on lesioned motoneurons and led to neuronal survival. Reactive gliosis and microglial reaction decreased in the same groups (AX+FS, AX+CFS) at 4 weeks. Regarding axonal regeneration, coaptation allowed recovery of greater number of myelinated fibers, with improved morphometric parameters. Preservation of inhibitory synaptic terminals was accompanied by significant improvement in the motor as well as in the nociceptive recovery. Overall, the present data suggest that acute repair of neonatal peripheral nerves with fibrin sealant results in neuroprotection and regeneration of motor and sensory axons. PMID:27446617

  6. Long-Standing Motor and Sensory Recovery following Acute Fibrin Sealant Based Neonatal Sciatic Nerve Repair

    PubMed Central

    Ferreira Junior, Rui Seabra

    2016-01-01

    Brachial plexus lesion results in loss of motor and sensory function, being more harmful in the neonate. Therefore, this study evaluated neuroprotection and regeneration after neonatal peripheral nerve coaptation with fibrin sealant. Thus, P2 neonatal Lewis rats were divided into three groups: AX: sciatic nerve axotomy (SNA) without treatment; AX+FS: SNA followed by end-to-end coaptation with fibrin sealant derived from snake venom; AX+CFS: SNA followed by end-to-end coaptation with commercial fibrin sealant. Results were analyzed 4, 8, and 12 weeks after lesion. Astrogliosis, microglial reaction, and synapse preservation were evaluated by immunohistochemistry. Neuronal survival, axonal regeneration, and ultrastructural changes at ventral spinal cord were also investigated. Sensory-motor recovery was behaviorally studied. Coaptation preserved synaptic covering on lesioned motoneurons and led to neuronal survival. Reactive gliosis and microglial reaction decreased in the same groups (AX+FS, AX+CFS) at 4 weeks. Regarding axonal regeneration, coaptation allowed recovery of greater number of myelinated fibers, with improved morphometric parameters. Preservation of inhibitory synaptic terminals was accompanied by significant improvement in the motor as well as in the nociceptive recovery. Overall, the present data suggest that acute repair of neonatal peripheral nerves with fibrin sealant results in neuroprotection and regeneration of motor and sensory axons. PMID:27446617

  7. Immediate and short-term pain relief by acute sciatic nerve press: a randomized controlled trial

    PubMed Central

    He, Jiman; Wu, Bin; Zhang, Wenlong; Ten, Guangping

    2007-01-01

    Background Despite much research, an immediately available, instantly effective and harmless pain relief technique has not been discovered. This study describes a new manipulation: a "2-minute sciatic nerve press", for rapid short-term relief of pain brought on by various dental and renal diseases. Methods This randomized, single-blind, placebo-controlled trial ran in three hospitals in Anhui Province, China, with an enrollment of 66 out of 111 solicited patients aged 16 to 74 years. Patients were recruited sequentially, by specific participating physicians at their clinic visits to three independent hospitals. The diseases in enrolled dental patients included dental caries, periodontal diseases and dental trauma. Renal diseases in recruits included kidney infections, stones and some other conditions. Patients were randomly assigned to receive the "2-minute sciatic nerve press" or the "placebo press". For the "2-minute sciatic nerve press", pressure was applied simultaneously to the sciatic nerves at the back of the thighs, using the fists while patients lay prone. For the "placebo press", pressure was applied simultaneously to a parallel spot on the front of the thighs, using the fists while patients lay supine. Each fist applied a pressure of 11 to 20 kg for 2 minutes, after which, patients arose to rate pain. Results The "2-minute sciatic nerve press" produced greater pain relief than the "placebo press". Within the first 10 minutes after sciatic pressure, immediate pain relief ratings averaged 66.4% (p < 0.001) for the dental patients, versus pain relief of 20% for the placebo press, and, 52.2% (p < 0.01) for the renal patients, versus relief of 14% for the placebo press, in median. The method worked excellently for dental caries and periodontal diseases, but poorly for dental trauma. Forty percent of renal patients with renal colic did not report any pain relief after the treatment. Conclusion Two minutes of pressure on both sciatic nerves can produce

  8. Acute electrophysiological effect of pulsed gallium-arsenide low-energy laser irradiation on isolated frog sciatic nerve.

    PubMed

    Cömelekoğlu, U; Bagiş, S; Büyükakilli, B; Sahin, G; Erdoğan, C; Kanik, A

    2002-01-01

    We evaluated the acute electrophysiological effects of low-energy pulsed laser irradiation on isolated frog sciatic nerve measured by extracellular recording technique. A pulsed gallium-arsenide (GaAs) laser (wavelength: 904 nm, pulse duration 220 ns, peak power per pulse: 27W, spot size: 0.28 cm(2), total applied energy density: 0.005-2.5J/cm(2)) was used for the experiment. Sixty isolated nerves were divided into six groups (n=10), each of which received a different laser dose. In each group, action potentials were recorded before laser irradiation which served as the control data. The extracellular action potentials were recorded for each combination of 1, 3, 5, 7, 10, 13 and 15 minutes of irradiation time and 4, 8, 16, 32, 64 and 128 repetition frequency by using a BIOPAC MP 100 Acquisition System Version 3.5.7 (Santa Barbara, USA). Action potential amplitude, area, duration and conduction velocity were measured. Statistical evaluation was performed using repeated measures variance analysis by SPSS 9.0. There were no statistically significant differences for action potential amplitude, area and conduction velocity among the laser groups and control data (p>0.05). The study showed that low-energy GaAs irradiation at 4-128 Hz repetition frequencies administered for irradiation times of 1-15 min generates no effect on action potential amplitude, area, duration and conduction velocity in isolated frog sciatic nerve.

  9. A Self-Administered Method of Acute Pressure Block of Sciatic Nerves for Short-Term Relief of Dental Pain: A Randomized Study

    PubMed Central

    Wang, Xiaolin; Zhao, Wanghong; Wang, Ye; Hu, Jiao; Chen, Qiu; Yu, Juncai; Wu, Bin; Huang, Rong; Gao, Jie; He, Jiman

    2014-01-01

    Objectives While stimulation of the peripheral nerves increases the pain threshold, chronic pressure stimulation of the sciatic nerve is associated with sciatica. We recently found that acute pressure block of the sciatic nerve inhibits pain. Therefore, we propose that, the pain pathology-causing pressure is chronic, not acute. Here, we report a novel self-administered method: acute pressure block of the sciatic nerves is applied by the patients themselves for short-term relief of pain from dental diseases. Design This was a randomized, single-blind study. Setting Hospital patients. Patients Patients aged 16–60 years with acute pulpitis, acute apical periodontitis, or pericoronitis of the third molar of the mandible experiencing pain ≥3 on the 11-point numerical pain rating scale. Interventions Three-minute pressure to sciatic nerves was applied by using the hands (hand pressure method) or by having the patients squat to force the thigh and shin as tightly as possible on the sandwiched sciatic nerve bundles (self-administered method). Outcomes The primary efficacy variable was the mean difference in pain scores from the baseline. Results One hundred seventy-two dental patients were randomized. The self-administered method produced significant relief from pain associated with dental diseases (P ≤ 0.001). The analgesic effect of the self-administered method was similar to that of the hand pressure method. Conclusions The self-administered method is easy to learn and can be applied at any time for pain relief. We believe that patients will benefit from this method. PMID:24400593

  10. Proximal Sciatic Nerve Intraneural Ganglion Cyst

    PubMed Central

    Swartz, Karin R.; Wilson, Dianne; Boland, Michael; Fee, Dominic B.

    2009-01-01

    Intraneural ganglion cysts are nonneoplastic, mucinous cysts within the epineurium of peripheral nerves which usually involve the peroneal nerve at the knee. A 37-year-old female presented with progressive left buttock and posterior thigh pain. Magnetic resonance imaging revealed a sciatic nerve mass at the sacral notch which was subsequently revealed to be an intraneural ganglion cyst. An intraneural ganglion cyst confined to the proximal sciatic nerve has only been reported once prior to 2009. PMID:20069041

  11. [Acute sciatic neuropathy--"post-Saturday palsy"].

    PubMed

    Manigoda, Miodrag; Dujmović-Basuroski, Irena; Trikić, Rajko; Drulović, Jelena

    2005-01-01

    This is a case report of 25-year old, unemployed male, admitted to hospital due to acute onset of the left foot drop, subsequent walking difficulty and numbness of the left calf and foot. Symptoms began after prolonged sleep with previous heroin abuse by sniffing. During neurological examination, mild weakness of knee flexors, moderate weakness of plantar flexors and paralysis of foot dorsiflexors, together with hypesthesia of the left calf, foot and fingers, predominantly in the innervation area of common peroneal nerve on the same side, were observed. The electrophysiologic examination revealed predominant involvement of peroneal division within the sciatic nerve, together with recorded conduction block indicating the compression as possible mechanism of nerve injury. The patient was administered corticosteroid therapy during two months, what resulted in almost complete recovery. The peculiarity of this case report is in the presence of the sciatic nerve "Saturday night palsy" with possible effect of former heroin abuse. PMID:16053177

  12. Acute Sciatic Neuritis following Lumbar Laminectomy

    PubMed Central

    Hitchon, Patrick; Reddy, Chandan G.

    2014-01-01

    It is commonly accepted that the common cause of acute/chronic pain in the distribution of the lumbosacral nerve roots is the herniation of a lumbar intervertebral disc, unless proven otherwise. The surgical treatment of lumbar disc herniation is successful in radicular pain and prevents or limits neurological damage in the majority of patients. Recurrence of sciatica after a successful disc surgery can be due to many possible etiologies. In the clinical setting we believe that the term sciatica might be associated with inflammation. We report a case of acute sciatic neuritis presented with significant persistent pain shortly after a successful disc surgery. The patient is a 59-year-old female with complaint of newly onset sciatica after complete pain resolution following a successful lumbar laminectomy for acute disc extrusion. In order to manage the patient's newly onset pain, the patient had multiple pain management visits which provided minimum relief. Persistent sciatica and consistent physical examination findings urged us to perform a pelvic MRI to visualize suspected pathology, which revealed right side sciatic neuritis. She responded to the electrical neuromodulation. Review of the literature on sciatic neuritis shows this is the first case report of sciatic neuritis subsequent to lumbar laminectomy. PMID:25024708

  13. Neurologic complication after anterior sciatic nerve block.

    PubMed

    Shah, Shruti; Hadzic, Admir; Vloka, Jerry D; Cafferty, Maureen S; Moucha, Calin S; Santos, Alan C

    2005-05-01

    The lack of reported complications related to lower extremity peripheral nerve blocks (PNBs) may be related to the relatively infrequent application of these techniques and to the fact that most such events go unpublished. Our current understanding of the factors that lead to neurologic complications after PNBs is limited. This is partly the result of our inability to conduct meaningful retrospective studies because of a lack of standard and objective monitoring and documentation procedures for PNBs. We report a case of permanent injury to the sciatic nerve after sciatic nerve block through the anterior approach and discuss mechanisms that may have led to the injury. Intraneural injection and nerve injury can occur in the absence of pain on injection and it may be heralded by high injection pressure (resistance).

  14. Correlative CT and anatomic study of the sciatic nerve

    SciTech Connect

    Pech, P.; Haughton, V.

    1985-05-01

    Sciatica can be caused by numerous processes affecting the sciatic nerve or its components within the pelvis including tumors, infectious diseases, aneurysms, fractures, and endometriosis. The CT diagnosis of these causes of sciatica has not been emphasized. This study identified the course and appearance of the normal sciatic nerve in the pelvis by correlating CT and anatomic slices in cadavers. For purposes of discussion, the sciatic nerve complex is conveniently divided into three parts: presacral, muscular, and ischial. Each part is illustrated here by two cryosections with corresponding CT images.

  15. Late sciatic nerve axonotmesis following acetabular reconstruction plate.

    PubMed

    Moreta, J; Foruria, X; Labayru, F

    2016-01-01

    Sciatic nerve injuries associated with acetabular fractures can be post-traumatic, perioperative or postoperative. Late postoperative injury is very uncommon and can be due to heterotopic ossifications, muscular scarring, or implant migration. A case is presented of a patient with a previous transverse acetabular fracture treated with a reconstruction plate for the posterior column. After 17 years, she presented with progressive pain and motor deficit in the sciatic territory. Radiological and neurophysiological assessments were performed and the patient underwent surgical decompression of the sciatic nerve. A transection of the nerve was observed that was due to extended compression of one of the screws. At 4 years postoperatively, her pain had substantially diminished and the paresthesias in her leg had resolved. However, her motor symptoms did not improve. This case report could be relevant due to this uncommon delayed sciatic nerve injury due to prolonged hardware impingement.

  16. Multivesicular liposomal bupivacaine at the sciatic nerve.

    PubMed

    McAlvin, J Brian; Padera, Robert F; Shankarappa, Sahadev A; Reznor, Gally; Kwon, Albert H; Chiang, Homer H; Yang, Jason; Kohane, Daniel S

    2014-05-01

    Clinical translation of sustained release formulations for local anesthetics has been limited by adverse tissue reaction. Exparel™ (DepoFoam bupivacaine) is a new liposomal local anesthetic formulation whose biocompatibility near nerve tissue is not well characterized. Exparel™ injection caused sciatic nerve blockade in rats lasting 240 min compared to 120 min for 0.5% (w/v) bupivacaine HCl and 210 min for 1.31% (w/v) bupivacaine HCl (same bupivacaine content as Exparel™). On histologic sections four days after injection, median inflammation scores in the Exparel™ group (2.5 of 4) were slightly higher than in groups treated with bupivacaine solutions (score 2). Myotoxicity scores in the Exparel™ group (2.5 of 6) were similar to in the 0.5% (w/v) bupivacaine HCl group (3), but significantly less than in the 1.31% (w/v) bupivacaine HCl group (5). After two weeks, inflammation from Exparel™ (score 2 of 6) was greater than from 0.5% (w/v) bupivacaine HCl (1) and similar to that from 1.31% (w/v) bupivacaine HCl (1). Myotoxicity in all three groups was not statistically significantly different. No neurotoxicity was detected in any group. Tissue reaction to Exparel™ was similar to that of 0.5% (w/v) bupivacaine HCl. Surveillance for local tissue injury will be important during future clinical evaluation.

  17. Effects of Alcohol Injection in Rat Sciatic Nerve

    PubMed Central

    Mazoch, Mathew J.; Cheema, Gulraiz A.; Suva, Larry J.; Thomas, Ruth L.

    2015-01-01

    Background Previous studies have shown that the injection of dehydrated alcohol has been successful for the treatment of Morton's neuroma in the foot. In this study, we determined the cellular effect of injection of alcohol into and around the sciatic nerve of rats, and measured the extent of cell necrosis and/or any associated histologic or inflammatory changes. Methods Twenty-two male (~375g) Wistar rats were randomized into two groups each receiving alcohol injections into or around the sciatic nerve after nerve exposure under sterile technique. Group 1 rats were injected with a 0.5ml solution of 0.5% Marcaine in the left sciatic nerve as a control group. In the right sciatic nerve a 0.5ml solution of 4% ethanol with 0.5% Marcaine was injected. Group 2 rats received 0.5ml of 20%ethanol with 0.5% Marcaine injected into the left sciatic nerve and 0.5 ml of 30% ethanol with 0.5% Marcaine injected into the right sciatic nerve. In each group, the rats were placed in 3 subgroups: intraneural, perineural, perimuscular injections. All rats were sacrificed and tissue harvested for histologic evaluation at day 10 post injection. Results No evidence of alcohol-associated cell necrosis, apoptosis or apparent inflammation was observed in histologic specimens of any injected nerves, perineural tissue, or muscles in controls or experimental groups regardless of concentration of ethanol injected on day 10. Conclusion We concluded that alcohol injection (≤30% ethanol) into and/or around the sciatic nerve or the adjacent muscle of rats has no histologic evidence of necrosis or inflammation to the nerve or surrounding tissue. There was no observable histological change in apoptosis, or cell number, in response to the alcohol injection. PMID:25097192

  18. Acute closed traumatic sciatic nerve injury: a complication of heterotopic ossification and prominence of the femoral nail: a case report.

    PubMed

    Niempoog, Sunyarn; Chumchuen, Sukanis

    2014-08-01

    The report of a 27-years-old man with presence of heterotopic ossification (HO) after femoral nailing 7years ago who developed foot drop afterfalling to the ground on his buttocks. Radiographs revealed a prominence ofthefemoral nail with HO in his right hip. EMG confirmedperoneal nerve injury ofthe hip region. Femoral nail and the HO were removed and external neurolysis was performed. At 9 months after surgery, he had not regain motor power thus posterior tibialis tendon transfer was performed to restore ankle dorsiflexion. Finally, at 2 years follow-up, he could ambulate well but did not regained sensation, extensor digitorum communis and peroneal muscle function. PMID:25518317

  19. Lower limb surgeries under combined femoral and sciatic nerve block

    PubMed Central

    Bansal, Lipsy; Attri, Joginder Pal; Verma, Pawan

    2016-01-01

    Introduction: Peripheral nerve blocks are gaining popularity for many infraumblical surgeries with the development of new techniques such as ultrasound and peripheral nerve stimulator. It provides stable hemodynamic, better, and prolonged postoperative analgesia. This study was carried out to see the effectiveness of combined femoral and sciatic nerve block with ropivacaine alone and by adding fentanyl. Materials and Methods: The study was carried out on 100 patients scheduled for lower limb surgeries and were randomly divided into two groups of 50 each. In Group A, patients received 20 ml of 0.5% ropivacaine for femoral nerve block and same dose for sciatic nerve block and in Group B, 25 μg fentanyl was added each for femoral nerve and sciatic nerve block along with ropivacaine. All hemodynamic parameters, onset and duration of sensory and motor blocks were noted. The patient characteristics were analyzed using the “Chi-square tests” and the intergroup comparison of the parametric data was carried out using the unpaired t-test using software IBM SPSS 17.0. Results: Combined femoral and sciatic nerve block provide longer duration of postoperative analgesia of about 12–13 h. All the above-mentioned parameters were statistically non-significant. Conclusion: Hence in this study, onset and duration of sensory and motor block was comparable in both groups. However postoperative analgesia was prolonged as compared to neuraxial blockade without any hemodynamic instability. PMID:27746528

  20. Histopathological effects of intramuscular metamizole sodium on rat sciatic nerve

    PubMed Central

    Emir, Abdurrahman; Kalkan, Yıldıray; Bostan, Habib

    2016-01-01

    Objective(s): We investigated the histopathological effects of metamizole sodium (MS) on the sciatic nerve. Materials and Methods: This study was performed using 48 adult male Wistar albino rats. Ten groups were constituted with 6 rats in each group. MS injection into the sciatic nerve (group 1), MS injection into the muscle [group 3 (50 mg/kg, 0.4 ml) and group 5 (50 mg/kg, 0.8 ml)], MS injection into the muscle cavity in the vicinity of the sciatic nerve [group 2 (50 mg/kg, 0.4 ml) and group 4 (50 mg/kg, 0.8 ml)], normal saline injection into the muscle in the vicinity of the sciatic nerve [group 6A (0.4 ml) and 6B (0.8 ml)], subjected to injury by drilling the entire layer of nerve without injecting any drug, normal saline injection in the sciatic nerve, and control group. Nerve and muscle samples were taken 7 days after administrations. Tissue sections were stained using a hematoxylin and eosin-Luxol® fast blue stain, assessed by a histologist. Results: The levels of axonal degeneration of the rats in groups 1, 2, 3, 4, 5, 6A, and 8 were found to be significantly higher compared to the levels of the rats in the control group (P<0.05). Myelin degeneration of the rats in all groups was found to be significantly higher compared to myelin degeneration of the rats in the control group (P<0.05). Conclusion: It was observed that MS could lead to injury in the sciatic nerve with a toxic effect due to diffusion. PMID:27746863

  1. The longitudinal epineural incision and complete nerve transection method for modeling sciatic nerve injury

    PubMed Central

    Cheng, Xing-long; Wang, Pei; Sun, Bo; Liu, Shi-bo; Gao, Yun-feng; He, Xin-ze; Yu, Chang-yu

    2015-01-01

    Injury severity, operative technique and nerve regeneration are important factors to consider when constructing a model of peripheral nerve injury. Here, we present a novel peripheral nerve injury model and compare it with the complete sciatic nerve transection method. In the experimental group, under a microscope, a 3-mm longitudinal incision was made in the epineurium of the sciatic nerve to reveal the nerve fibers, which were then transected. The small, longitudinal incision in the epineurium was then sutured closed, requiring no stump anastomosis. In the control group, the sciatic nerve was completely transected, and the epineurium was repaired by anastomosis. At 2 and 4 weeks after surgery, Wallerian degeneration was observed in both groups. In the experimental group, at 8 and 12 weeks after surgery, distinct medullary nerve fibers and axons were observed in the injured sciatic nerve. Regular, dense myelin sheaths were visible, as well as some scarring. By 12 weeks, the myelin sheaths were normal and intact, and a tight lamellar structure was observed. Functionally, limb movement and nerve conduction recovered in the injured region between 4 and 12 weeks. The present results demonstrate that longitudinal epineural incision with nerve transection can stably replicate a model of Sunderland grade IV peripheral nerve injury. Compared with the complete sciatic nerve transection model, our method reduced the difficulties of micromanipulation and surgery time, and resulted in good stump restoration, nerve regeneration, and functional recovery. PMID:26692866

  2. Chronic sciatic nerve compression induces fibrosis in dorsal root ganglia.

    PubMed

    Li, Qinwen; Chen, Jianghai; Chen, Yanhua; Cong, Xiaobin; Chen, Zhenbing

    2016-03-01

    In the present study, pathological alterations in neurons of the dorsal root ganglia (DRG) were investigated in a rat model of chronic sciatic nerve compression. The rat model of chronic sciatic nerve compression was established by placing a 1 cm Silastic tube around the right sciatic nerve. Histological examination was performed via Masson's trichrome staining. DRG injury was assessed using Fluoro Ruby (FR) or Fluoro Gold (FG). The expression levels of target genes were examined using reverse transcription‑quantitative polymerase chain reaction, western blot and immunohistochemical analyses. At 3 weeks post‑compression, collagen fiber accumulation was observed in the ipsilateral area and, at 8 weeks, excessive collagen formation with muscle atrophy was observed. The collagen volume fraction gradually and significantly increased following sciatic nerve compression. In the model rats, the numbers of FR‑labeled DRG neurons were significantly higher, relative to the sham‑operated group, however, the numbers of FG‑labeled neurons were similar. In the ipsilateral DRG neurons of the model group, the levels of transforming growth factor‑β1 (TGF‑β1) and connective tissue growth factor (CTGF) were elevated and, surrounding the neurons, the levels of collagen type I were increased, compared with those in the contralateral DRG. In the ipsilateral DRG, chronic nerve compression was associated with significantly higher levels of phosphorylated (p)‑extracellular signal‑regulated kinase 1/2, and significantly lower levels of p‑c‑Jun N‑terminal kinase and p‑p38, compared with those in the contralateral DRGs. Chronic sciatic nerve compression likely induced DRG pathology by upregulating the expression levels of TGF‑β1, CTGF and collagen type I, with involvement of the mitogen‑activated protein kinase signaling pathway. PMID:26820076

  3. Nanofibrous nerve conduits for repair of 30-mm-long sciatic nerve defects

    PubMed Central

    Biazar, Esmaeil; Keshel, Saeed Heidari; Pouya, Majid; Rad, Hadi; Nava, Melody Omrani; Azarbakhsh, Mohammad; Hooshmand, Shirin

    2013-01-01

    It has been confirmed that nanofibrous poly(3-hydroxybutyrate-co-3-hydroxyvalerate) nerve conduit can promote peripheral nerve regeneration in rats. However, its efficiency in repair of over 30-mm-long sciatic nerve defects needs to be assessed. In this study, we used a nanofibrous poly(3-hydroxybutyrate-co-3-hydroxyvalerate) nerve conduit to bridge a 30-mm-long gap in the rat sciatic nerve. At 4 months after nerve conduit implantation, regenerated nerves were cally observed and histologically assessed. In the nanofibrous graft, the rat sciatic nerve trunk had been reconstructed by restoration of nerve continuity and formation of myelinated nerve fiber. There were Schwann cells and glial cells in the regenerated nerves. Masson's trichrome staining showed that there were no pathological changes in the size and structure of gastrocnemius muscle cells on the operated side of rats. These findings suggest that nanofibrous poly(3-hydroxybutyrate-co-3-hydroxyvalerate) nerve conduit is suitable for repair of long-segment sciatic nerve defects. PMID:25206536

  4. Poly(lactic-co-glycolic acid) conduit for repair of injured sciatic nerve: A mechanical analysis

    PubMed Central

    Yu, Tao; Zhao, Changfu; Li, Peng; Liu, Guangyao; Luo, Min

    2013-01-01

    Tensile stress and tensile strain directly affect the quality of nerve regeneration after bridging nerve defects by poly(lactic-co-glycolic acid) conduit transplantation and autogenous nerve grafting for sciatic nerve injury. This study collected the sciatic nerve from the gluteus maximus muscle from fresh human cadaver, and established 10-mm-long sciatic nerve injury models by removing the ischium, following which poly(lactic-co-glycolic acid) conduits or autogenous nerve grafts were transplanted. Scanning electron microscopy revealed that the axon and myelin sheath were torn, and the vessels of basilar membrane were obstructed in the poly(lactic-co-glycolic acid) conduit-repaired sciatic nerve following tensile testing. There were no significant differences in tensile tests with autogenous nerve graft-repaired sciatic nerve. Following poly(lactic-co-glycolic acid) conduit transplantation for sciatic nerve repair, tensile test results suggest that maximum tensile load, maximum stress, elastic limit load and elastic limit stress increased compared with autogenous nerve grafts, but elastic limit strain and maximum strain decreased. Moreover, the tendencies of stress-strain curves of sciatic nerves were similar after transplantation of poly(lactic-co-glycolic acid) conduits or autogenous nerve grafts. Results showed that after transplantation in vitro for sciatic nerve injury, poly(lactic-co-glycolic acid) conduits exhibited good intensity, elasticity and plasticity, indicating that poly(lactic-co-glycolic acid) conduits are suitable for sciatic nerve injury repair. PMID:25206505

  5. Poly(lactic-co-glycolic acid) conduit for repair of injured sciatic nerve: A mechanical analysis.

    PubMed

    Yu, Tao; Zhao, Changfu; Li, Peng; Liu, Guangyao; Luo, Min

    2013-07-25

    Tensile stress and tensile strain directly affect the quality of nerve regeneration after bridging nerve defects by poly(lactic-co-glycolic acid) conduit transplantation and autogenous nerve grafting for sciatic nerve injury. This study collected the sciatic nerve from the gluteus maximus muscle from fresh human cadaver, and established 10-mm-long sciatic nerve injury models by removing the ischium, following which poly(lactic-co-glycolic acid) conduits or autogenous nerve grafts were transplanted. Scanning electron microscopy revealed that the axon and myelin sheath were torn, and the vessels of basilar membrane were obstructed in the poly(lactic-co-glycolic acid) conduit-repaired sciatic nerve following tensile testing. There were no significant differences in tensile tests with autogenous nerve graft-repaired sciatic nerve. Following poly(lactic-co-glycolic acid) conduit transplantation for sciatic nerve repair, tensile test results suggest that maximum tensile load, maximum stress, elastic limit load and elastic limit stress increased compared with autogenous nerve grafts, but elastic limit strain and maximum strain decreased. Moreover, the tendencies of stress-strain curves of sciatic nerves were similar after transplantation of poly(lactic-co-glycolic acid) conduits or autogenous nerve grafts. Results showed that after transplantation in vitro for sciatic nerve injury, poly(lactic-co-glycolic acid) conduits exhibited good intensity, elasticity and plasticity, indicating that poly(lactic-co-glycolic acid) conduits are suitable for sciatic nerve injury repair.

  6. Changes in contralateral protein metabolism following unilateral sciatic nerve section

    SciTech Connect

    Menendez, J.A.; Cubas, S.C.

    1990-03-01

    Changes in nerve biochemistry, anatomy, and function following injuries to the contralateral nerve have been repeatedly reported, though their significance is unknown. The most likely mechanisms for their development are either substances carried by axoplasmic flow or electrically transmitted signals. This study analyzes which mechanism underlies the development of a contralateral change in protein metabolism. The incorporation of labelled amino acids (AA) into proteins of both sciatic nerves was assessed by liquid scintillation after an unilateral section. AA were offered locally for 30 min to the distal stump of the sectioned nerves and at homologous levels of the intact contralateral nerves. At various times, from 1 to 24 h, both sciatic nerves were removed and the proteins extracted with trichloroacetic acid (TCA). An increase in incorporation was found in both nerves 14-24 h after section. No difference existed between sectioned and intact nerves, which is consistent with the contralateral effect. Lidocaine, but not colchicine, when applied previously to the nerves midway between the sectioning site and the spinal cord, inhibited the contralateral increase in AA incorporation. It is concluded that electrical signals, crossing through the spinal cord, are responsible for the development of the contralateral effect. Both the nature of the proteins and the significance of the contralateral effect are matters for speculation.

  7. Sciatic nerve repair using adhesive bonding and a modified conduit

    PubMed Central

    Liang, Xiangdang; Cai, Hongfei; Hao, Yongyu; Sun, Geng; Song, Yaoyao; Chen, Wen

    2014-01-01

    When repairing nerves with adhesives, most researchers place glue directly on the nerve stumps, but this method does not fix the nerve ends well and allows glue to easily invade the nerve ends. In this study, we established a rat model of completely transected sciatic nerve injury and repaired it using a modified 1 cm-length conduit with inner diameter of 1.5 mm. Each end of the cylindrical conduit contains a short linear channel, while the enclosed central tube protects the nerve ends well. Nerves were repaired with 2-octyl-cyanoacrylate and suture, which complement the function of the modified conduit. The results demonstrated that for the same conduit, the average operation time using the adhesive method was much shorter than with the suture method. No significant differences were found between the two groups in sciatic function index, motor evoked potential latency, motor evoked potential amplitude, muscular recovery rate, number of medullated nerve fibers, axon diameter, or medullary sheath thickness. Thus, the adhesive method for repairing nerves using a modified conduit is feasible and effective, and reduces the operation time while providing an equivalent repair effect. PMID:25206861

  8. Immune cell distribution and immunoglobulin levels change following sciatic nerve injury in a rat model

    PubMed Central

    Yuan, Wei; Feng, Xinhong

    2016-01-01

    Objective(s): To investigate the systemic and local immune status of two surgical rat models of sciatic nerve injury, a crushed sciatic nerve, and a sciatic nerve transection Materials and Methods: Twenty-four adult male Sprague-Dawley rats were randomly divided into three groups: sham-operation (control group), sciatic nerve crush, and sciatic nerve transaction. Sciatic nerve surgery was performed. The percentage of CD4+ cells and the CD4+/CD8+ratio were determined by flow cytometry. Serum IgM and IgG levels were analyzed by ELISA. T-cells (CD3) and macrophages (CD68) in sciatic nerve tissue sections were identified through immunohistochemistry. Results: Compared to sham-operated controls, in rats that underwent nerve injury, the percentage of CD4+ cells and the CD4+/CD8+ ratio in the peripheral blood were significantly decreased 7 days after surgery, serum IgM levels were increased 14 days after surgery, and serum IgG levels were increased 21 days after surgery. There were a large number of CD3+ cells and a small number of CD68+ cells in sciatic nerve tissue sections 21 days after surgery, indicating T-cell and macrophage activation and infiltration. Local IgG deposition was also detected at the nerve injury site 21 days after surgery. Conclusion: Rat humoral and cellular immune status changed following sciatic nerve injury, particularly with regard to the cellular immune response at the nerve injury site.

  9. Immune cell distribution and immunoglobulin levels change following sciatic nerve injury in a rat model

    PubMed Central

    Yuan, Wei; Feng, Xinhong

    2016-01-01

    Objective(s): To investigate the systemic and local immune status of two surgical rat models of sciatic nerve injury, a crushed sciatic nerve, and a sciatic nerve transection Materials and Methods: Twenty-four adult male Sprague-Dawley rats were randomly divided into three groups: sham-operation (control group), sciatic nerve crush, and sciatic nerve transaction. Sciatic nerve surgery was performed. The percentage of CD4+ cells and the CD4+/CD8+ratio were determined by flow cytometry. Serum IgM and IgG levels were analyzed by ELISA. T-cells (CD3) and macrophages (CD68) in sciatic nerve tissue sections were identified through immunohistochemistry. Results: Compared to sham-operated controls, in rats that underwent nerve injury, the percentage of CD4+ cells and the CD4+/CD8+ ratio in the peripheral blood were significantly decreased 7 days after surgery, serum IgM levels were increased 14 days after surgery, and serum IgG levels were increased 21 days after surgery. There were a large number of CD3+ cells and a small number of CD68+ cells in sciatic nerve tissue sections 21 days after surgery, indicating T-cell and macrophage activation and infiltration. Local IgG deposition was also detected at the nerve injury site 21 days after surgery. Conclusion: Rat humoral and cellular immune status changed following sciatic nerve injury, particularly with regard to the cellular immune response at the nerve injury site. PMID:27635205

  10. Efficacy of nanofibrous conduits in repair of long-segment sciatic nerve defects

    PubMed Central

    Biazar, Esmaeil; Keshel, Saeed Heidari; Pouya, Majid

    2013-01-01

    Our previous studies have histomorphologically confirmed that nanofibrous poly(3-hydroxybutyrate-co-3-hydroxyvalerate) conduit can be used to repair 30-mm-long sciatic nerve defects. However, the repair effects on rat behaviors remain poorly understood. In this study, we used nanofibrous poly(3-hydroxybutyrate-co-3-hydroxyvalerate) conduit and autologous sciatic nerve to bridge 30-mm-long rat sciatic nerve gaps. Within 4 months after surgery, rat sciatic nerve functional recovery was evaluated per month by behavioral analyses, including toe out angle, toe spread analysis, walking track analysis, extensor postural thrust, swimming test, open-field analysis and nociceptive function. Results showed that rat sciatic nerve functional recovery was similar after nanofibrous poly(3-hydroxybutyrate-co-3-hydroxyvalerate) conduit and autologous nerve grafting. These findings suggest that nanofibrous poly(3-hydroxybutyrate-co-3-hydroxyvalerate) conduit is suitable in use for repair of long-segment sciatic nerve defects. PMID:25206560

  11. Biomechanical and functional variation in rat sciatic nerve following cuff electrode implantation

    PubMed Central

    2014-01-01

    Background Nerve cuff electrodes are commonly and successfully used for stimulating peripheral nerves. On the other hand, they occasionally induce functional and morphological changes following chronic implantation, for reasons not always clear. We hypothesize that restriction of nerve mobility due to cuff implantation may alter nerve conduction. Methods We quantified acute changes in nerve-muscle electrophysiology, using electromyography, and nerve kinematics in anesthetized Sprague Dawley rat sciatic nerves during controlled hindlimb joint movement. We compared electrophysiological and biomechanical response in uncuffed nerves and those secured within a cuff electrode using analysis of variance (ANOVA) and regression analysis. Results Tethering resulting from cuff implantation resulted in altered nerve strain and a complex biomechanical environment during joint movement. Coincident with biomechanical changes, electromyography revealed significantly increased variability in the response of conduction latency and amplitude in cuffed, but not free, nerves following joint movement. Conclusion Our findings emphasize the importance of the mechanical interface between peripheral nerves and their devices on neurophysiological performance. This work has implications for nerve device design, implantation, and prediction of long-term efficacy. PMID:24758405

  12. Application of implantable wireless biomicrosystem for monitoring nerve impedance of rat after sciatic nerve injury.

    PubMed

    Li, Yu-Ting; Peng, Chih-Wei; Chen, Lung-Tai; Lin, Wen-Shan; Chu, Chun-Hsun; Chen, Jia-Jin Jason

    2013-01-01

    Electrical stimulation is usually applied percutaneously for facilitating peripheral nerve regeneration. However, few studies have conducted long-term monitoring of the condition of nerve regeneration. This study implements an implantable biomicrosystem for inducing pulse current for aiding nerve repair and monitoring the time-course changes of nerve impedance for assessing nerve regeneration in sciatic nerve injury rat model. For long-term implantation, a transcutaneous magnetic coupling technique is adopted for power and data transmission. For in vivo study, the implanted module was placed in the rat's abdomen and the cuff electrode was wrapped around an 8-mm sciatic nerve gap of the rat for nerve impedance measurement for 42 days. One group of animals received monophasic constant current via the cuff electrode and a second group had no stimulation between days 8-21. The nerve impedance increased to above 150% of the initial value in the nerve regeneration groups with and without stimulation whereas the group with no nerve regeneration increased to only 113% at day 42. The impedance increase in nerve regeneration groups can be observed before evident functional recovery. Also, the nerve regeneration group that received electrical stimulation had relatively higher myelinated fiber density than that of no stimulation group, 20686 versus 11417 fiber/mm (2). The developed implantable biomicrosystem is proven to be a useful experimental tool for long-term stimulation in aiding nerve fiber growth as well as impedance assessment for understanding the time-course changes of nerve regeneration. PMID:23060343

  13. The Sciatic Nerve Cuffing Model of Neuropathic Pain in Mice

    PubMed Central

    Yalcin, Ipek; Megat, Salim; Barthas, Florent; Waltisperger, Elisabeth; Kremer, Mélanie; Salvat, Eric; Barrot, Michel

    2014-01-01

    Neuropathic pain arises as a consequence of a lesion or a disease affecting the somatosensory system. This syndrome results from maladaptive changes in injured sensory neurons and along the entire nociceptive pathway within the central nervous system. It is usually chronic and challenging to treat. In order to study neuropathic pain and its treatments, different models have been developed in rodents. These models derive from known etiologies, thus reproducing peripheral nerve injuries, central injuries, and metabolic-, infectious- or chemotherapy-related neuropathies. Murine models of peripheral nerve injury often target the sciatic nerve which is easy to access and allows nociceptive tests on the hind paw. These models rely on a compression and/or a section. Here, the detailed surgery procedure for the "cuff model" of neuropathic pain in mice is described. In this model, a cuff of PE-20 polyethylene tubing of standardized length (2 mm) is unilaterally implanted around the main branch of the sciatic nerve. It induces a long-lasting mechanical allodynia, i.e., a nociceptive response to a normally non-nociceptive stimulus that can be evaluated by using von Frey filaments. Besides the detailed surgery and testing procedures, the interest of this model for the study of neuropathic pain mechanism, for the study of neuropathic pain sensory and anxiodepressive aspects, and for the study of neuropathic pain treatments are also discussed. PMID:25078668

  14. The sciatic nerve cuffing model of neuropathic pain in mice.

    PubMed

    Yalcin, Ipek; Megat, Salim; Barthas, Florent; Waltisperger, Elisabeth; Kremer, Mélanie; Salvat, Eric; Barrot, Michel

    2014-07-16

    Neuropathic pain arises as a consequence of a lesion or a disease affecting the somatosensory system. This syndrome results from maladaptive changes in injured sensory neurons and along the entire nociceptive pathway within the central nervous system. It is usually chronic and challenging to treat. In order to study neuropathic pain and its treatments, different models have been developed in rodents. These models derive from known etiologies, thus reproducing peripheral nerve injuries, central injuries, and metabolic-, infectious- or chemotherapy-related neuropathies. Murine models of peripheral nerve injury often target the sciatic nerve which is easy to access and allows nociceptive tests on the hind paw. These models rely on a compression and/or a section. Here, the detailed surgery procedure for the "cuff model" of neuropathic pain in mice is described. In this model, a cuff of PE-20 polyethylene tubing of standardized length (2 mm) is unilaterally implanted around the main branch of the sciatic nerve. It induces a long-lasting mechanical allodynia, i.e., a nociceptive response to a normally non-nociceptive stimulus that can be evaluated by using von Frey filaments. Besides the detailed surgery and testing procedures, the interest of this model for the study of neuropathic pain mechanism, for the study of neuropathic pain sensory and anxiodepressive aspects, and for the study of neuropathic pain treatments are also discussed.

  15. The effect of ubiquinone on functional recovery and morphometric indices of sciatic nerve regeneration

    PubMed Central

    Moradi, Z; Azizi, S; Hobbenaghi, R

    2014-01-01

    A common cause of peripheral nerve injury is trauma. The positive effect of antioxidants on the improvement of nerve regeneration has currently become a focus of attention. In this experiment, the effect of intraperitoneal administration of ubiquinone (CoQ10) on an acute experimentally sciatic nerve crush was studied in a rat model. Forty-five male Wistar rats, weighing between 160-180 g were used. The rats were randomly divided into two experimental groups (n=20). Each group was further subdivided into four subgroups of five animals each. Functional studies confirmed the faster recovery of regenerated axons in the treatment group compared to the un-treated group (P<0.05). Morphometric indices of the regenerated fibers showed the number and diameter of the myelinated fibers to be significantly higher in the treatment group than the un-treated group (P<0.05). Intraperitoneal administration of CoQ10 (10 mg/kg/day) in the early inflammatory stage of sciatic nerve crush was found to improve nerve regeneration. PMID:27175137

  16. Diabetic neuropathy increases stimulation threshold during popliteal sciatic nerve block†

    PubMed Central

    Heschl, S.; Hallmann, B.; Zilke, T.; Gemes, G.; Schoerghuber, M.; Auer-Grumbach, M.; Quehenberger, F.; Lirk, P.; Hogan, Q.; Rigaud, M.

    2016-01-01

    Background Peripheral nerve stimulation is commonly used for nerve localization in regional anaesthesia, but recommended stimulation currents of 0.3–0.5 mA do not reliably produce motor activity in the absence of intraneural needle placement. As this may be particularly true in patients with diabetic neuropathy, we examined the stimulation threshold in patients with and without diabetes. Methods Preoperative evaluation included a neurological exam and electroneurography. During ultrasound-guided popliteal sciatic nerve block, we measured the current required to produce motor activity for the tibial and common peroneal nerve in diabetic and non-diabetic patients. Proximity to the nerve was evaluated post-hoc using ultrasound imaging. Results Average stimulation currents did not differ between diabetic (n=55) and non-diabetic patients (n=52). Although the planned number of patients was not reached, the power goal for the mean stimulation current was met. Subjects with diminished pressure perception showed increased thresholds for the common peroneal nerve (median 1.30 vs. 0.57 mA in subjects with normal perception, P=0.042), as did subjects with decreased pain sensation (1.60 vs. 0.50 mA in subjects with normal sensation, P=0.038). Slowed ulnar nerve conduction velocity predicted elevated mean stimulation current (r=−0.35, P=0.002). Finally, 15 diabetic patients required more than 0.5 mA to evoke a motor response, despite intraneural needle placement (n=4), or required currents ≥2 mA despite needle-nerve contact, vs three such patients (1 intraneural, 2 with ≥2 mA) among non-diabetic patients (P=0.003). Conclusions These findings suggest that stimulation thresholds of 0.3–0.5 mA may not reliably determine close needle-nerve contact during popliteal sciatic nerve block, particularly in patients with diabetic neuropathy. Clinical trial registration NCT01488474 PMID:26994231

  17. [Method of studying the microcirculation of the sciatic nerve during life].

    PubMed

    Razumova, I L; Chernukh, A M

    1977-02-01

    The authors describe a mehtod of bloodless exposure of the sciatic nerve in rats, of placing it on the light conductor, and of the preparation of microscope MBI-6 for the intravital study of microhemocirculation in the epineurium of the sciatic nerve. Different types of the microvessel network of rat are demonstrated.

  18. Effect of Frankincense Extract on Nerve Recovery in the Rat Sciatic Nerve Damage Model

    PubMed Central

    Jiang, Xiaowen; Ma, Jun; Wei, Qingwei; Feng, Xinxin; Qiao, Lu; Liu, Lin; Zhang, Binqing; Yu, Wenhui

    2016-01-01

    This study investigated the effect of frankincense extract on peripheral nerve regeneration in a crush injury rat model. Forty-eight Sprague-Dawley rats were randomly divided into four groups: control and frankincense extract low-, medium-, and high-dose groups. At days 7, 14, 21, and 28 following the surgery, nerve regeneration and functional recovery were evaluated using the sciatic functional index (SFI), expression of GAP-43, and the proliferation of Schwann cells (SCs) in vivo and in vitro. At day 7, the SFI in the frankincense extract high-dose group was significantly improved compared with the control group. After day 14, SFI was significantly improved in the medium- and high-dose groups. There was no significant difference in GAP-43 expression among the groups at day 7. However, after day 14, expression of GAP-43 in the high-dose group was higher than that in the control group. Histological evaluation showed that the injured nerve of frankincense extract high-dose group recovered better than the other groups 28 days after surgery. Further, S100 immunohistochemical staining, MTT colorimetry, and flow cytometry assays all showed that frankincense extract could promote the proliferation of SCs. In conclusion, frankincense extract is able to promote sciatic nerve regeneration and improve the function of a crushed sciatic nerve. This study provides a new direction for the repair of peripheral nerve injury. PMID:27143985

  19. Mesenchymal Stem Cells Enhance Nerve Regeneration in a Rat Sciatic Nerve Repair and Hindlimb Transplant Model

    PubMed Central

    Cooney, Damon S.; Wimmers, Eric G.; Ibrahim, Zuhaib; Grahammer, Johanna; Christensen, Joani M.; Brat, Gabriel A.; Wu, Lehao W.; Sarhane, Karim A.; Lopez, Joseph; Wallner, Christoph; Furtmüller, Georg J.; Yuan, Nance; Pang, John; Sarkar, Kakali; Lee, W. P. Andrew; Brandacher, Gerald

    2016-01-01

    This study investigates the efficacy of local and intravenous mesenchymal stem cell (MSC) administration to augment neuroregeneration in both a sciatic nerve cut-and-repair and rat hindlimb transplant model. Bone marrow-derived MSCs were harvested and purified from Brown-Norway (BN) rats. Sciatic nerve transections and repairs were performed in three groups of Lewis (LEW) rats: negative controls (n = 4), local MSCs (epineural) injection (n = 4), and systemic MSCs (intravenous) injection (n = 4). Syngeneic (LEW-LEW) (n = 4) and allogeneic (BN-LEW) (n = 4) hindlimb transplants were performed and assessed for neuroregeneration after local or systemic MSC treatment. Rats undergoing sciatic nerve cut-and-repair and treated with either local or systemic injection of MSCs had significant improvement in the speed of recovery of compound muscle action potential amplitudes and axon counts when compared with negative controls. Similarly, rats undergoing allogeneic hindlimb transplants treated with local injection of MSCs exhibited significantly increased axon counts. Similarly, systemic MSC treatment resulted in improved nerve regeneration following allogeneic hindlimb transplants. Systemic administration had a more pronounced effect on electromotor recovery while local injection was more effective at increasing fiber counts, suggesting different targets of action. Local and systemic MSC injections significantly improve the pace and degree of nerve regeneration after nerve injury and hindlimb transplantation. PMID:27510321

  20. Mesenchymal Stem Cells Enhance Nerve Regeneration in a Rat Sciatic Nerve Repair and Hindlimb Transplant Model.

    PubMed

    Cooney, Damon S; Wimmers, Eric G; Ibrahim, Zuhaib; Grahammer, Johanna; Christensen, Joani M; Brat, Gabriel A; Wu, Lehao W; Sarhane, Karim A; Lopez, Joseph; Wallner, Christoph; Furtmüller, Georg J; Yuan, Nance; Pang, John; Sarkar, Kakali; Lee, W P Andrew; Brandacher, Gerald

    2016-01-01

    This study investigates the efficacy of local and intravenous mesenchymal stem cell (MSC) administration to augment neuroregeneration in both a sciatic nerve cut-and-repair and rat hindlimb transplant model. Bone marrow-derived MSCs were harvested and purified from Brown-Norway (BN) rats. Sciatic nerve transections and repairs were performed in three groups of Lewis (LEW) rats: negative controls (n = 4), local MSCs (epineural) injection (n = 4), and systemic MSCs (intravenous) injection (n = 4). Syngeneic (LEW-LEW) (n = 4) and allogeneic (BN-LEW) (n = 4) hindlimb transplants were performed and assessed for neuroregeneration after local or systemic MSC treatment. Rats undergoing sciatic nerve cut-and-repair and treated with either local or systemic injection of MSCs had significant improvement in the speed of recovery of compound muscle action potential amplitudes and axon counts when compared with negative controls. Similarly, rats undergoing allogeneic hindlimb transplants treated with local injection of MSCs exhibited significantly increased axon counts. Similarly, systemic MSC treatment resulted in improved nerve regeneration following allogeneic hindlimb transplants. Systemic administration had a more pronounced effect on electromotor recovery while local injection was more effective at increasing fiber counts, suggesting different targets of action. Local and systemic MSC injections significantly improve the pace and degree of nerve regeneration after nerve injury and hindlimb transplantation. PMID:27510321

  1. Human distal sciatic nerve fascicular anatomy: implications for ankle control using nerve-cuff electrodes.

    PubMed

    Gustafson, Kenneth J; Grinberg, Yanina; Joseph, Sheeba; Triolo, Ronald J

    2012-01-01

    The design of neural prostheses to restore standing balance, prevent foot drop, or provide active propulsion during ambulation requires detailed knowledge of the distal sciatic nerve anatomy. Three complete sciatic nerves and branches were dissected from the piriformis to each muscle entry point to characterize the branching patterns and diameters. Fascicle maps were created from serial sections of each distal terminus below the knee through the anastomosis of the tibial and common fibular nerves above the knee. Similar branching patterns and fascicle maps were observed across specimens. Fascicles innervating primary plantar flexors, dorsiflexors, invertors, and evertors were distinctly separate and functionally organized in the proximal tibial, common fibular, and distal sciatic nerves; however, fascicles from individual muscles were not apparent at these levels. The fascicular organization is conducive to selective stimulation for isolated and/or balanced dorsiflexion, plantar flexion, eversion, and inversion through a single multicontact nerve-cuff electrode. These neuroanatomical data are being used to design nerve-cuff electrodes for selective control of ankle movement and improve current lower-limb neural prostheses. PMID:22773531

  2. Lentiviral-mediated transfer of CDNF promotes nerve regeneration and functional recovery after sciatic nerve injury in adult rats

    SciTech Connect

    Cheng, Lei; Liu, Yi; Zhao, Hua; Zhang, Wen; Guo, Ying-Jun; Nie, Lin

    2013-10-18

    Highlights: •CDNF was successfully transfected by a lentiviral vector into the distal sciatic nerve. •CDNF improved S-100, NF200 expression and nerve regeneration after sciatic injury. •CDNF improved the remyelination and thickness of the regenerated sciatic nerve. •CDNF improved gastrocnemius muscle weight and sciatic functional recovery. -- Abstract: Peripheral nerve injury is often followed by incomplete and unsatisfactory functional recovery and may be associated with sensory and motor impairment of the affected limb. Therefore, a novel method is needed to improve the speed of recovery and the final functional outcome after peripheral nerve injuries. This report investigates the effect of lentiviral-mediated transfer of conserved dopamine neurotrophic factor (CDNF) on regeneration of the rat peripheral nerve in a transection model in vivo. We observed notable overexpression of CDNF protein in the distal sciatic nerve after recombinant CDNF lentiviral vector application. We evaluated sciatic nerve regeneration after surgery using light and electron microscopy and the functional recovery using the sciatic functional index and target muscle weight. HE staining revealed better ordered structured in the CDNF-treated group at 8 weeks post-surgery. Quantitative analysis of immunohistochemistry of NF200 and S-100 in the CDNF group revealed significant improvement of axonal and Schwann cell regeneration compared with the control groups at 4 weeks and 8 weeks after injury. The thickness of the myelination around the axons in the CDNF group was significantly higher than in the control groups at 8 weeks post-surgery. The CDNF group displayed higher muscle weights and significantly increased sciatic nerve index values. Our findings suggest that CDNF gene therapy could provide durable and stable CDNF protein concentration and has the potential to enhance peripheral nerve regeneration, morphological and functional recovery following nerve injury, which suggests a

  3. Diffusion tensor magnetic resonance imaging of regeneration/degeneration after rat sciatic nerve injury

    NASA Astrophysics Data System (ADS)

    Sig Hwang, Min; Perrin, George; Muir, David; Mareci, Thomas

    2005-11-01

    Diffusion tensor imaging was performed to investigate myelination and demyelination spatiotemporally in cut or crushed excised rat sciatic nerves in a 17.6 T magnet with a solenoid RF coil. Orientation independent measures of water diffusion, fractional anisotropy (FA) and averaged diffusivity (), were examined as MR parameters for the quantification of the myelin within the major peripheral nerve. Crushed nerves initially demonstrated decreased FA, followed by increase to FA of normal nerve with time. At 14 days post injury, FA of the nerve is high, 0.85, at the site proximal to the injury then FA decreases in a proximodistal gradient because the nerve remains more demyelinated toward the distal area. Cut sciatic nerves displayed a prolonged decrease of FA with time after injury. Also FA correlates with in these nerves. Therefore FA or may be a good indicator of myelination and demyelination in rat sciatic nerves and FA appears to be a more sensitive indicator of myelin.

  4. Differential temporal expression of matrix metalloproteinases following sciatic nerve crush.

    PubMed

    Qin, Jing; Zha, Guang-Bin; Yu, Jun; Zhang, Hong-Hong; Yi, Sheng

    2016-07-01

    We previously performed transcriptome sequencing and found that genes for matrix metalloproteinases (MMPs), such as MMP7 and 12, seem to be highly upregulated following peripheral nerve injury, and may be involved in nerve repair. In the present study, we systematically determined the expression levels of MMPs and their regulators at 1, 4, 7 and 14 days after sciatic nerve crush injury. The number of differentially expressed genes was elevated at 4 and 7 days after injury, but decreased at 14 days after injury. Among the differentially expressed genes, those most up-regulated showed fold changes of more than 214, while those most down-regulated exhibited fold changes of more than 2-10. Gene sequencing showed that, at all time points after injury, a variety of MMP genes in the "Inhibition of MMPs" pathway were up-regulated, and their inhibitor genes were down-regulated. Expression of key up- and down-regulated genes was verified by quantitative real-time polymerase chain reaction analysis and found to be consistent with transcriptome sequencing. These results suggest that MMP-related genes are strongly involved in the process of peripheral nerve regeneration. PMID:27630704

  5. Differential temporal expression of matrix metalloproteinases following sciatic nerve crush

    PubMed Central

    Qin, Jing; Zha, Guang-bin; Yu, Jun; Zhang, Hong-hong; Yi, Sheng

    2016-01-01

    We previously performed transcriptome sequencing and found that genes for matrix metalloproteinases (MMPs), such as MMP7 and 12, seem to be highly upregulated following peripheral nerve injury, and may be involved in nerve repair. In the present study, we systematically determined the expression levels of MMPs and their regulators at 1, 4, 7 and 14 days after sciatic nerve crush injury. The number of differentially expressed genes was elevated at 4 and 7 days after injury, but decreased at 14 days after injury. Among the differentially expressed genes, those most up-regulated showed fold changes of more than 214, while those most down-regulated exhibited fold changes of more than 2−10. Gene sequencing showed that, at all time points after injury, a variety of MMP genes in the “Inhibition of MMPs” pathway were up-regulated, and their inhibitor genes were down-regulated. Expression of key up- and down-regulated genes was verified by quantitative real-time polymerase chain reaction analysis and found to be consistent with transcriptome sequencing. These results suggest that MMP-related genes are strongly involved in the process of peripheral nerve regeneration. PMID:27630704

  6. Topography of Synchronization of Somatosensory Evoked Potentials Elicited by Stimulation of the Sciatic Nerve in Rat

    PubMed Central

    Qu, Xuefeng; Yan, Jiaqing; Li, Xiaoli; Zhang, Peixun; Liu, Xianzeng

    2016-01-01

    Purpose: Traditionally, the topography of somatosensory evoked potentials (SEPs) is generated based on amplitude and latency. However, this operation focuses on the physical morphology and field potential-power, so it suffers from difficulties in performing identification in an objective manner. In this study, measurement of the synchronization of SEPs is proposed as a method to explore brain functional networks as well as the plasticity after peripheral nerve injury. Method: SEPs elicited by unilateral sciatic nerve stimulation in twelve adult male Sprague-Dawley (SD) rats in the normal group were compared with SEPs evoked after unilateral sciatic nerve hemisection in four peripheral nerve injured SD rats. The characterization of synchronized networks from SEPs was conducted using equal-time correlation, correlation matrix analysis, and comparison to randomized surrogate data. Eigenvalues of the correlation matrix were used to identify the clusters of functionally synchronized neuronal activity, and the participation index (PI) was calculated to indicate the involvement of each channel in the cluster. The PI value at the knee point of the PI histogram was used as a threshold to demarcate the cortical boundary. Results: Ten out of the twelve normal rats showed only one synchronized brain network. The remaining two normal rats showed one strong and one weak network. In the peripheral nerve injured group, only one synchronized brain network was found in each rat. In the normal group, all network shapes appear regular and the network is largely contained in the posterior cortex. In the injured group, the network shapes appear irregular, the network extends anteriorly and posteriorly, and the network area is significantly larger. There are considerable individual variations in the shape and location of the network after peripheral nerve injury. Conclusion: The proposed method can detect functional brain networks. Compared to the results of the traditional SEP

  7. Sciatic nerve injury related to hip replacement surgery: imaging detection by MR neurography despite susceptibility artifacts.

    PubMed

    Wolf, Marcel; Bäumer, Philipp; Pedro, Maria; Dombert, Thomas; Staub, Frank; Heiland, Sabine; Bendszus, Martin; Pham, Mirko

    2014-01-01

    Sciatic nerve palsy related to hip replacement surgery (HRS) is among the most common causes of sciatic neuropathies. The sciatic nerve may be injured by various different periprocedural mechanisms. The precise localization and extension of the nerve lesion, the determination of nerve continuity, lesion severity, and fascicular lesion distribution are essential for assessing the potential of spontaneous recovery and thereby avoiding delayed or inappropriate therapy. Adequate therapy is in many cases limited to conservative management, but in certain cases early surgical exploration and release of the nerve is indicated. Nerve-conduction-studies and electromyography are essential in the diagnosis of nerve injuries. In postsurgical nerve injuries, additional diagnostic imaging is important as well, in particular to detect or rule out direct mechanical compromise. Especially in the presence of metallic implants, commonly applied diagnostic imaging tests generally fail to adequately visualize nervous tissue. MRI has been deemed problematic due to implant-related artifacts after HRS. In this study, we describe for the first time the spectrum of imaging findings of Magnetic Resonance neurography (MRN) employing pulse sequences relatively insensitive to susceptibility artifacts (susceptibility insensitive MRN, siMRN) in a series of 9 patients with HRS procedure related sciatic nerve palsy. We were able to determine the localization and fascicular distribution of the sciatic nerve lesion in all 9 patients, which clearly showed on imaging predominant involvement of the peroneal more than the tibial division of the sciatic nerve. In 2 patients siMRN revealed direct mechanical compromise of the nerve by surgical material, and in one of these cases indication for surgical release of the sciatic nerve was based on siMRN. Thus, in selected cases of HRS related neuropathies, especially when surgical exploration of the nerve is considered, siMRN, with its potential to largely

  8. Repeated activation of delta opioid receptors counteracts nerve injury-induced TNF-α up-regulation in the sciatic nerve of rats with neuropathic pain

    PubMed Central

    Vicario, Nunzio; Parenti, Rosalba; Aricò, Giuseppina; Turnaturi, Rita; Scoto, Giovanna Maria; Chiechio, Santina

    2016-01-01

    Despite mu opioid receptor agonists are the cornerstones of moderate-to-severe acute pain treatment, their effectiveness in chronic pain conditions is controversial. In contrast to mu opioid receptor agonists, a number of studies have reported the effectiveness of delta opioid receptor agonists on neuropathic pain strengthening the idea that delta opioid receptors gain importance when chronic pain develops. Among other effects, it has been shown that delta opioid receptor activation in optic nerve astrocytes inhibits tumor necrosis factor-α-mediated inflammation in response to severe hypoxia. Considering the involvement of tumor necrosis factor-α in the development and maintenance of neuropathic pain, with this study we sought to correlate the effect of delta opioid receptor agonist on the development of mechanical allodynia to tumor necrosis factor-α expression at the site of nerve injury in rats subjected to chronic constriction injury of the sciatic nerve. To this aim, we measured the levels of tumor necrosis factor-α in the sciatic nerve of rats with neuropathic pain after repeated injections with a delta opioid receptor agonist. Results obtained demonstrated that repeated administrations of the delta opioid receptor agonist SNC80 (10 mg/kg, i.p. for seven consecutive days) significantly inhibited the development of mechanical allodynia in rats with neuropathic pain and that the improvement of neuropathic symptom was timely related to the reduced expression of tumor necrosis factor-α in the rat sciatic nerve. We demonstrated also that when treatment with the delta opioid receptor agonist was suspended both allodynia and tumor necrosis factor-α up-regulation in the sciatic nerve of rats with neuropathic pain were restored. These results show that persistent delta opioid receptor activation significantly attenuates neuropathic pain and negatively regulates sciatic nerve tumor necrosis factor-α expression in chronic constriction injury rats. PMID:27590071

  9. Giant Lipomatosis of the Sciatic Nerve: Unique Magnetic Resonance Imaging Findings.

    PubMed

    Sarp, Ali Firat; Pekcevik, Yeliz

    2016-04-01

    Lipomatosis of the nerve, also known as fibrolipomatous hamartoma, is characterized by the infiltration of the nerve by fibro-fatty tissue. The affected nerve becomes thicker, and it simulates a mass lesion. Lipomatosis usually affects the median nerve and lipomatosis of the sciatic nerve is extremely rare. Magnetic resonance imaging (MRI) is the key to diagnosis, and it is usually pathognomonic. In this report, MRI and diffusion-weighted MRI findings of a case of a giant sciatic nerve lipomatosis without macrodactyly are presented. The MRI findings are unique, and awareness of the MRI features of this rare soft tissue mass may prevent unnecessary biopsies and surgeries. PMID:27679695

  10. Giant Lipomatosis of the Sciatic Nerve: Unique Magnetic Resonance Imaging Findings

    PubMed Central

    Sarp, Ali Firat; Pekcevik, Yeliz

    2016-01-01

    Lipomatosis of the nerve, also known as fibrolipomatous hamartoma, is characterized by the infiltration of the nerve by fibro-fatty tissue. The affected nerve becomes thicker, and it simulates a mass lesion. Lipomatosis usually affects the median nerve and lipomatosis of the sciatic nerve is extremely rare. Magnetic resonance imaging (MRI) is the key to diagnosis, and it is usually pathognomonic. In this report, MRI and diffusion-weighted MRI findings of a case of a giant sciatic nerve lipomatosis without macrodactyly are presented. The MRI findings are unique, and awareness of the MRI features of this rare soft tissue mass may prevent unnecessary biopsies and surgeries.

  11. Giant Lipomatosis of the Sciatic Nerve: Unique Magnetic Resonance Imaging Findings

    PubMed Central

    Sarp, Ali Firat; Pekcevik, Yeliz

    2016-01-01

    Lipomatosis of the nerve, also known as fibrolipomatous hamartoma, is characterized by the infiltration of the nerve by fibro-fatty tissue. The affected nerve becomes thicker, and it simulates a mass lesion. Lipomatosis usually affects the median nerve and lipomatosis of the sciatic nerve is extremely rare. Magnetic resonance imaging (MRI) is the key to diagnosis, and it is usually pathognomonic. In this report, MRI and diffusion-weighted MRI findings of a case of a giant sciatic nerve lipomatosis without macrodactyly are presented. The MRI findings are unique, and awareness of the MRI features of this rare soft tissue mass may prevent unnecessary biopsies and surgeries. PMID:27679695

  12. Effects of sciatic nerve stimulation on the propagation of cortical spreading depression

    NASA Astrophysics Data System (ADS)

    Sun, Xiaoli; Yu, Zhidong; Zeng, Shaoqun; Luo, Qingming; Li, Pengcheng

    2008-02-01

    Cortical spreading depression (CSD) is an important pathological model of migraine and is related to other neural disorders, such as cerebral ischemia and epilepsy. It has been reported that brain stimulation is a quite effective way to treat neural diseases. However, direct stimulation could cause harm to brain. If peripheral nerve stimulation could have the same treatment, it would be essential to investigate the mechanisms of peripheral nerve and the study of sciatic nerve stimulation would have profound clinical meaning. In this paper, we used optical intrinsic signal imaging (OISI) and extracellular electrophysiologic recording techniques to study the effects of sciatic nerve stimulation on the propagation of CSD. We found that: (1) continuous sciatic nerve stimulation on rats caused a decrease in light intensity on the whole cortex, which meant an increase in cerebral blood volume(CBV); (2) the spreading velocity of CSD declined from 3.63+/- 0.272 mm/min to 3.06+/-0.260 mm/min during sciatic nerve stimulation, compared with that without sciatic nerve stimulation. In summary, data suggests that sciatic nerve stimulation elicits a response of cortex and causes a slowdown in the propagation of CSD.

  13. Low-level laser irradiation improves functional recovery and nerve regeneration in sciatic nerve crush rat injury model.

    PubMed

    Wang, Chau-Zen; Chen, Yi-Jen; Wang, Yan-Hsiung; Yeh, Ming-Long; Huang, Mao-Hsiung; Ho, Mei-Ling; Liang, Jen-I; Chen, Chia-Hsin

    2014-01-01

    The development of noninvasive approaches to facilitate the regeneration of post-traumatic nerve injury is important for clinical rehabilitation. In this study, we investigated the effective dose of noninvasive 808-nm low-level laser therapy (LLLT) on sciatic nerve crush rat injury model. Thirty-six male Sprague Dawley rats were divided into 6 experimental groups: a normal group with or without 808-nm LLLT at 8 J/cm(2) and a sciatic nerve crush injury group with or without 808-nm LLLT at 3, 8 or 15 J/cm(2). Rats were given consecutive transcutaneous LLLT at the crush site and sacrificed 20 days after the crush injury. Functional assessments of nerve regeneration were analyzed using the sciatic functional index (SFI) and hindlimb range of motion (ROM). Nerve regeneration was investigated by measuring the myelin sheath thickness of the sciatic nerve using transmission electron microscopy (TEM) and by analyzing the expression of growth-associated protein 43 (GAP43) in sciatic nerve using western blot and immunofluorescence staining. We found that sciatic-injured rats that were irradiated with LLLT at both 3 and 8 J/cm(2) had significantly improved SFI but that a significant improvement of ROM was only found in rats with LLLT at 8 J/cm(2). Furthermore, the myelin sheath thickness and GAP43 expression levels were significantly enhanced in sciatic nerve-crushed rats receiving 808-nm LLLT at 3 and 8 J/cm(2). Taken together, these results suggest that 808-nm LLLT at a low energy density (3 J/cm(2) and 8 J/cm(2)) is capable of enhancing sciatic nerve regeneration following a crush injury. PMID:25119457

  14. (-)-Epigallocatechin-3-gallate (EGCG) attenuates peripheral nerve degeneration in rat sciatic nerve crush injury.

    PubMed

    Renno, Waleed M; Al-Maghrebi, May; Alshammari, Ahmad; George, Preethi

    2013-02-01

    Recently, we have shown that green tea (GT) consumption improves both reflexes and sensation in unilateral chronic constriction injury to the sciatic nerve. Considering the substantial neuroprotective properties of GT polyphenols, we sought to investigate whether (-)-epigallocatechin-3-gallate (EGCG) could protect the sciatic nerve and improve functional impairments induced by a crushing injury. We also examined whether neuronal cell apoptosis induced by the crushing injury is affected by EGCG treatment. Histological examination of sciatic nerves from EGCG-treated (50mg/kg; i.p.) showed that axonotmized rats had a remarkable axonal and myelin regeneration with significant decrease in the number of myelinated axonal fibers compared to vehicle-treated crush group. Similarly, ultrastructural evaluation of EGCG-treated nerves displayed normal unmyelinated and myelinated axons with regular myelin sheath thickness and normalized appearance of Schmidt-Lantermann clefts. Extracellular matrix displayed normal collagen fibers appearance with distinctively organized distribution similar to sham animals. Analysis of foot position and extensor postural thrust test showed a progressive and faster recovery in the EGCG-treated group compared to vehicle-treated animals. EGCG-treated rats showed significant increase in paw withdrawal thresholds to mechanical stimulation compared to vehicle-treated crush group. EGCG treatment also restored the mRNA expression of Bax, Bcl-2 and survivin but not that of p53 to sham levels on days 3 and 7 post-injury. Our results demonstrate that EGCG treatment enhanced functional recovery, advanced morphological nerve rescue and accelerated nerve regeneration following crush injury partly due to the down regulation of apoptosis related genes. PMID:23313191

  15. Endoscopic Sciatic Nerve Decompression in the Prone Position-An Ischial-Based Approach.

    PubMed

    Jackson, Timothy J

    2016-06-01

    Deep gluteal syndrome is described as sciatic nerve entrapment in the region deep to the gluteus maximus muscle. The entrapment can occur from the piriformis muscle, fibrous bands, blood vessels, and hamstrings. Good clinical outcomes have been shown in patients treated by open and endoscopic means. Sciatic nerve decompression with or without piriformis release provides a surgical solution to a difficult diagnostic and therapeutic problem. Previous techniques have used open methods that can now performed endoscopically. The technique of an endoscopic approach to sciatic nerve decompression in the prone position is described as well as its advantages and common findings. Through this ischial-based approach, a familiar anatomy is seen and areas of sciatic nerve entrapment can be readily identified and safely decompressed. PMID:27656390

  16. [Composite resection of sciatic nerve for local recurrence of rectal cancer].

    PubMed

    Kameyama, M; Nakamori, S; Imaoka, S; Hinakawa, M; Sasaki, Y; Ishikawa, O; Kabuto, T; Furukawa, H; Iwanaga, T; Ueda, T

    1993-08-01

    Three patients with local recurrence of rectal cancer involving the sciatic nerve underwent radical pelvic exenteration combined with sciatic nerve resection. This surgical procedure resulted in complete relief of intolerable cancer pain in all patients. After the rehabilitation, all could walk unassisted by wearing only a below-the-knee leg brace. The first patient died 16 months postoperatively due to multiple liver metastasis, but no local recurrence was documented. The second patient is alive 13 months postoperatively with bone and liver metastasis and pelvic wall recurrence. The third patient is alive 7 months postoperatively with no evidence of disease. Composite resection of lateral sciatic nerve improved the quality of life in patients who had local recurrence of rectal cancer with sciatic nerve involvement.

  17. Inhibition of nerve conduction by electromagnetic induction of the frog sciatic nerve-gastrocnemius muscle preparation.

    PubMed

    Wali, F A; Brain, A I

    1989-01-01

    The effect of electromagnetic induction (EMI) on impulse conduction and muscle contraction was studied in isolated sciatic nerve-gastrocnemius muscle preparation of the frog. Electrical stimulation (ES) of the sciatic nerve, at 0.5 Hz with 0.6 V (supramaximal) and 1-ms pulse duration, produced twitch contractions (3.5 +/- 0.4 g tension, mean +/- S.E., n = 8 frogs), which were reduced or blocked by EMI, applied to the nerve via an induction coil, from a d.c. source of 1.5-4 V, at a frequency of 100 min-1, for 2- to 4-min duration. Recovery of the blocked twitches was obtained within 4-5 min, after the cessation of the EMI and washing out the preparation in Ringer solution. The inhibition of the twitch tension by EMI was compared to that produced by an effective concentration of a local anaesthetic, lignocaine (1 microM), which is known to block conduction, by blocking ionic fluxes across the nerve membrane. It is possible that EMI also interferes with the ionic fluxes, and in prolonged duration, may produce changes in the myelin sheath (or the Schwann cells) of the nerve membrane. A comparison of ES with EMI was made, and it was concluded that EMI inhibited electrically induced neuromuscular transmission at the frog neuromuscular junction.

  18. Redoxins in peripheral neurons after sciatic nerve injury.

    PubMed

    Valek, Lucie; Kanngießer, Maike; Häussler, Annett; Agarwal, Nitin; Lillig, Christopher Horst; Tegeder, Irmgard

    2015-12-01

    Peripheral nerve injury causes redox stress in injured neurons by upregulations of pro-oxidative enzymes, but most neurons survive suggesting an activation of endogenous defense against the imbalance. As potential candidates we assessed thioredoxin-fold proteins, called redoxins, which maintain redox homeostasis by reduction of hydrogen peroxide or protein dithiol-disulfide exchange. Using a histologic approach, we show that the peroxiredoxins (Prdx1-6), the glutaredoxins (Glrx1, 2, 3 and 5), thioredoxin (Txn1 and 2) and their reductases (Txnrd1 and 2) are expressed in neurons, glial and/or vascular cells of the dorsal root ganglia (DRGs) and in the spinal cord. They show distinct cellular and subcellular locations in agreement with the GO terms for "cellular component". The expression and localization of Glrx, Txn and Txnrd proteins was not affected by sciatic nerve injury but peroxiredoxins were upregulated in the DRGs, Prdx1 and Prdx6 mainly in non-neuronal cells and Prdx4 and Prdx5 in DRG neurons, the latter associated with an increase of respective mRNAs and protein accumulation in peripheral and/or central fibers. The upregulation of Prdx4 and Prdx5 in DRG neurons was reduced in mice with a cre-loxP mediated deficiency of hypoxia inducible factor 1 alpha (HIF1α) in these neurons. The results identify Prdx4 and Prdx5 as endogenous HIF1α-dependent, transcriptionally regulated defenders of nerve injury evoked redox stress that may be important for neuronal survival and regeneration.

  19. Presentation of Neurolytic Effect of 10% Lidocaine after Perineural Ultrasound Guided Injection of a Canine Sciatic Nerve: A Pilot Study

    PubMed Central

    Asif, Asma; Kataria, Sandeep

    2016-01-01

    Background Phenol and alcohol have been used to ablate nerves to treat pain but are not specific for nerves and can damage surrounding soft tissue. Lidocaine at concentrations > 8% injected intrathecal in the animal model has been shown to be neurotoxic. Tests the hypothesis that 10% lidocaine is neurolytic after a peri-neural blockade in an ex vivo experiment on the canine sciatic nerve. Methods Under ultrasound, one canine sciatic nerve was injected peri-neurally with 10 cc saline and another with 10 cc of 10% lidocaine. After 20 minutes, the sciatic nerve was dissected with gross inspection. A 3 cm segment was excised and preserved in 10% buffered formalin fixative solution. Both samples underwent progressive dehydration and infusion of paraffin after which they were placed on paraffin blocks. The sections were cut at 4 µm and stained with hemoxylin and eosin. Microscopic review was performed by a pathologist from Henry Ford Hospital who was blinded to which experimental group each sample was in. Results The lidocaine injected nerve demonstrated loss of gross architecture on visual inspection while the saline injected nerve did not. No gross changes were seen in the surrounding soft tissue seen in either group. The lidocaine injected sample showed basophilic degeneration with marked cytoplasmic vacuolation in the nerve fibers with separation of individual fibers and endoneurial edema. The saline injected sample showed normal neural tissue. Conclusions Ten percent lidocaine causes rapid neurolytic changes with ultrasound guided peri-neural injection. The study was limited by only a single nerve being tested with acute exposure. PMID:27413480

  20. Allograft pretreatment for the repair of sciatic nerve defects: green tea polyphenols versus radiation

    PubMed Central

    Zhou, Sheng-hu; Zhen, Ping; Li, Shen-song; Liang, Xiao-yan; Gao, Ming-xuan; Tian, Qi; Li, Xu-sheng

    2015-01-01

    Pretreatment of nerve allografts by exposure to irradiation or green tea polyphenols can eliminate neuroimmunogenicity, inhibit early immunological rejection, encourage nerve regeneration and functional recovery, improve tissue preservation, and minimize postoperative infection. In the present study, we investigate which intervention achieves better results. We produced a 1.0 cm sciatic nerve defect in rats, and divided the rats into four treatment groups: autograft, fresh nerve allograft, green tea polyphenol-pretreated (1 mg/mL, 4°C) nerve allograft, and irradiation-pretreated nerve allograft (26.39 Gy/min for 12 hours; total 19 kGy). The animals were observed, and sciatic nerve electrophysiology, histology, and transmission electron microscopy were carried out at 6 and 12 weeks after grafting. The circumference and structure of the transplanted nerve in rats that received autografts or green tea polyphenol-pretreated nerve allografts were similar to those of the host sciatic nerve. Compared with the groups that received fresh or irradiation-pretreated nerve allografts, motor nerve conduction velocity in the autograft and fresh nerve allograft groups was greater, more neurites grew into the allografts, Schwann cell proliferation was evident, and a large number of new blood vessels was observed; in addition, massive myelinated nerve fibers formed, and abundant microfilaments and microtubules were present in the axoplasm. Our findings indicate that nerve allografts pretreated by green tea polyphenols are equivalent to transplanting autologous nerves in the repair of sciatic nerve defects, and promote nerve regeneration. Pretreatment using green tea polyphenols is better than pretreatment with irradiation. PMID:25788934

  1. Pain clinic #15. Treatment of sciatic nerve causalgia following pelvic fracture.

    PubMed

    Sullivan, R J; Thomas, P S; Geel, C V

    1990-06-01

    Direct injury to the sciatic nerve may occur in patients who sustain acetabular/pelvic fractures. Sciatic nerve causalgia has been noted in patients who suffer posterior wall acetabular fracture with or without ipsilateral hip dislocation. Sympathetic nervous system dysfunction is considered the primary cause for this syndrome, although some investigators suggest central nervous system involvement. This report documents the treatment results of three patients suffering from sciatic nerve causalgia who were referred to the Pain Treatment Center during the past year. In each case, diagnosis was confirmed by sympathetic blockade. Treatment regimens varied and included nerve blocks, cryoanalgesia techniques, and transcutaneous electrical nerve stimulation therapy. The syndrome was relieved in these patients within four to six weeks. Patients were followed for six months after initial treatment. PMID:2367147

  2. Polylactic-co-glycolic acid microspheres containing three neurotrophic factors promote sciatic nerve repair after injury

    PubMed Central

    Zhao, Qun; Li, Zhi-yue; Zhang, Ze-peng; Mo, Zhou-yun; Chen, Shi-jie; Xiang, Si-yu; Zhang, Qing-shan; Xue, Min

    2015-01-01

    A variety of neurotrophic factors have been shown to repair the damaged peripheral nerve. However, in clinical practice, nerve growth factor, neurotrophin-3 and brain-derived neurotrophic factor are all peptides or proteins that may be rapidly deactivated at the focal injury site; their local effective concentration time following a single medication cannot meet the required time for spinal axons to regenerate and cross the glial scar. In this study, we produced polymer sustained-release microspheres based on the polylactic-co-glycolic acid copolymer; the microspheres at 300-μm diameter contained nerve growth factor, neurotrophin-3 and brain-derived neurotrophic factor. Six microspheres were longitudinally implanted into the sciatic nerve at the anastomosis site, serving as the experimental group; while the sciatic nerve in the control group was subjected to the end-to-end anastomosis using 10/0 suture thread. At 6 weeks after implantation, the lower limb activity, weight of triceps surae muscle, sciatic nerve conduction velocity and the maximum amplitude were obviously better in the experimental group than in the control group. Compared with the control group, more regenerating nerve fibers were observed and distributed in a dense and ordered manner with thicker myelin sheaths in the experimental group. More angiogenesis was also visible. Experimental findings indicate that polylactic-co-glycolic acid composite microspheres containing nerve growth factor, neurotrophin-3 and brain-derived neurotrophic factor can promote the restoration of sciatic nerve in rats after injury. PMID:26604912

  3. Reactive oxygen species (ROS) mediates non-freezing cold injury of rat sciatic nerve

    PubMed Central

    Geng, Zhiwei; Tong, Xiaoyan; Jia, Hongjuan

    2015-01-01

    Non-freezing cold injury is an injury characterized by neuropathy, developing when patients expose to cold environments. Reactive oxygen species (ROS) has been shown as a contributing factor for the non-freezing cold nerve injury. However, the detailed connections between non-freezing cold nerve injury and ROS have not been described. In order to investigate the relationship between non-freezing cold nerve injury and reactive oxygen species, we study the effects of two cooling methods-the continuous cooling and the intermittent cooling with warming intervals-on rat sciatic nerves. Specifically, we assess the morphological changes and ROS production of the sciatic nerves underwent different cooling treatments. Our data shows both types of cooling methods cause nerve injury and ROS production. However, despite of identical cooling degree and duration, the sciatic nerves processed by intermittent cooling with warming intervals present more ROS production, severer reperfusion injury and pathological destructions than the sciatic nerves processed by continuous cooling. This result indicates reactive oxygen species, as a product of reperfusion, facilitates non-freezing cold nerve injury. PMID:26629065

  4. Detection of Position-Related Sciatic Nerve Dysfunction by Somatosensory Evoked Potentials During Spinal Surgery.

    PubMed

    Rice, Kent; Scott, Andrew; Guyot, Anne

    2015-06-01

    It is well established that intraoperative somatosensory evoked potentials (SSEPs) are sensitive to plexus and peripheral nerve dysfunction related to malpositioning of patients during spinal surgery. While most reports focus on upper extremity nerve or brachial plexus effects, there is very little on detection of sciatic nerve compromise. Recording of the SSEP at the popliteal fossa is a common strategy to aid in troubleshooting stimulus-related problems or distal peripheral tibial nerve failure; yet position-related sciatic nerve effects may not be realized by changes in the popliteal fossa response. Three posterior lumbar surgeries are reviewed in which there was evidence of proximal lower extremity peripheral nerve dysfunction related to positioning. Loss of posterior tibial nerve SSEPs with preservation of the peripheral popliteal fossa response recording occurred in the absence of critical surgical manipulations. Efforts at repositioning and release of tension on the lower limbs promptly resulted in recovey of lost responses. Two of the three cases involved patients in a kneeling position with a tight strap across the posterior thigh. Standard SSEP recordings used in intraoperative neuromonitoring do not specifically localize intraoperative changes to the sciatic nerve; thus, such changes affecting SSEPs above the popliteal fossa mimic iatrogenic changes occurring at the surgical site. These case reports show that when the stage of surgery does not support iatrogenic changes, malpositioning affecting sciatic nerve should be considered, especially for patients placed in a kneeling position on an Andrews frame.

  5. Polylactic-co-glycolic acid microspheres containing three neurotrophic factors promote sciatic nerve repair after injury.

    PubMed

    Zhao, Qun; Li, Zhi-Yue; Zhang, Ze-Peng; Mo, Zhou-Yun; Chen, Shi-Jie; Xiang, Si-Yu; Zhang, Qing-Shan; Xue, Min

    2015-09-01

    A variety of neurotrophic factors have been shown to repair the damaged peripheral nerve. However, in clinical practice, nerve growth factor, neurotrophin-3 and brain-derived neurotrophic factor are all peptides or proteins that may be rapidly deactivated at the focal injury site; their local effective concentration time following a single medication cannot meet the required time for spinal axons to regenerate and cross the glial scar. In this study, we produced polymer sustained-release microspheres based on the polylactic-co-glycolic acid copolymer; the microspheres at 300-μm diameter contained nerve growth factor, neurotrophin-3 and brain-derived neurotrophic factor. Six microspheres were longitudinally implanted into the sciatic nerve at the anastomosis site, serving as the experimental group; while the sciatic nerve in the control group was subjected to the end-to-end anastomosis using 10/0 suture thread. At 6 weeks after implantation, the lower limb activity, weight of triceps surae muscle, sciatic nerve conduction velocity and the maximum amplitude were obviously better in the experimental group than in the control group. Compared with the control group, more regenerating nerve fibers were observed and distributed in a dense and ordered manner with thicker myelin sheaths in the experimental group. More angiogenesis was also visible. Experimental findings indicate that polylactic-co-glycolic acid composite microspheres containing nerve growth factor, neurotrophin-3 and brain-derived neurotrophic factor can promote the restoration of sciatic nerve in rats after injury.

  6. The effect of pregabalin - codeine combination on partial sciatic nerve ligation - induced peripheral mononeuropathy in rats.

    PubMed

    Popa, G; Mititelu Tartau, L; Stoleriu, I; Lupusoru, R V; Lupusoru, C E; Ochiuz, L

    2016-06-01

    The present study investigates the effects of pregabalin (PGB) and codeine (COD) combination on neuropathic hyperalgesia in an animal model of peripheral nerve injury represented by partial sciatic nerve ligation. Hot plate and analgesimeter tests were performed to evaluate the influence of PGB, COD and their combination on thermal and mechanical hyperalgesia in the hind paw with partial sciatic nerve ligation. Reactivity was evaluated by measuring the latency to withdrawal of the operated hind paw from the noxious heat and pressure stimulation. Nociceptive thresholds were evaluated before (baseline) and in the 1(st), 3(rd), 5(th) and 7(th) day after surgical procedure. The investigation demonstrates that the treatment with PGB attenuated partial sciatic nerve ligation development of thermal and mechanical hyperalgesia in rats operated hind paw. The oral administration, during 14 consecutive days of PGB-COD combination significantly reduced the degree of both thermal and mechanical hyperalgesia in the hind paw with partial sciatic nerve ligation. These results suggest that the association of PGB with COD exerted ameliorative effect on partial sciatic nerve ligation-induced neuropathic pain in rats. PMID:27512007

  7. Delayed Presentation of Sciatic Nerve Injury after Total Hip Arthroplasty: Neurosurgical Considerations, Diagnosis, and Management

    PubMed Central

    Xu, Linda W.; Veeravagu, Anand; Azad, Tej D.; Harraher, Ciara; Ratliff, John K.

    2016-01-01

    Background  Total hip arthroplasty (THA) is an established treatment for end-stage arthritis, congenital deformity, and trauma with good long-term clinical and functional outcomes. Delayed sciatic nerve injury is a rare complication after THA that requires prompt diagnosis and management. Methods  We present a case of sciatic nerve motor and sensory deficit in a 52-year-old patient 2 years after index left THA. Electromyography (EMG) results and imaging with radiographs and CT of the affected hip demonstrated an aberrant acetabular cup screw in the posterior-inferior quadrant adjacent to the sciatic nerve. Case Description  The patient underwent surgical exploration that revealed injury to the peroneal division of the sciatic nerve due to direct injury from screw impingement. A literature review identified 11 patients with late-onset neuropathy after THA. Ten patients underwent surgical exploration and pain often resolved after surgery with 56% of patients recovering sensory function and 25% experiencing full recovery of motor function. Conclusions  Delayed neuropathy of the sciatic nerve is a rare complication after THA that is most often due to hardware irritation, component failure, or wear-related pseudotumor formation. Operative intervention is often pursued to explore and directly visualize the nerve with limited results in the literature showing modest relief of pain and sensory symptoms and poor restoration of motor function. PMID:27602309

  8. Polyethylene Glycol-Fused Allografts Produce Rapid Behavioral Recovery After Ablation of Sciatic Nerve Segments

    PubMed Central

    Riley, D.C.; Bittner, G.D.; Mikesh, M.A.; Cardwell, N.L.; Pollins, A.C.; Ghergherehchi, C.L.; Sunkesula, S.R. Bhupanapadu; Ha, T.N.; Hall, B.T.D.; Poon, A.D.; Pyarali, M.; Boyer, R.B.; Mazal, A.T.; Munoz, N.; Trevino, R.C.; Schallert, T.; Thayer, W.P.

    2014-01-01

    Restoration of neuronal functions by outgrowths regenerating at ~1mm/d from the proximal stumps of severed peripheral nerves takes many weeks or months, if it occurs at all, especially after ablation of nerve segments. Distal segments of severed axons typically degenerate in 1–3 days. The purpose of this study was to show that Wallerian degeneration could be prevented or retarded and lost behavioral function restored following ablation of 0.5 – 1 cm segments of rat sciatic nerves in host animals. This is achieved using 0.8 – 1.1cm microsutured donor allografts treated with bioengineered solutions varying in ionic and polyethylene glycol (PEG) concentrations (modified PEG-fusion procedure), being careful not to stretch any portion of donor or host sciatic nerves. Our data show that PEG-fusion permanently restores axonal continuity within minutes as initially assessed by action potential conduction and intracellular diffusion of dye. Behavioral functions mediated by the sciatic nerve are largely restored within 2 – 4 wk as measured by the Sciatic Functional Index (SFI). Increased restoration of sciatic behavioral functions after ablating 0.5 – 1 cm segments is associated with greater numbers of viable myelinated axons within, and distal to, PEG-fused allografts. Many such viable myelinated axons are almost-certainly spared from Wallerian degeneration by PEG-fusion. PEG-fusion of donor allografts may produce a paradigm-shift in the treatment of peripheral nerve injuries. PMID:25425242

  9. Delayed Presentation of Sciatic Nerve Injury after Total Hip Arthroplasty: Neurosurgical Considerations, Diagnosis, and Management

    PubMed Central

    Xu, Linda W.; Veeravagu, Anand; Azad, Tej D.; Harraher, Ciara; Ratliff, John K.

    2016-01-01

    Background  Total hip arthroplasty (THA) is an established treatment for end-stage arthritis, congenital deformity, and trauma with good long-term clinical and functional outcomes. Delayed sciatic nerve injury is a rare complication after THA that requires prompt diagnosis and management. Methods  We present a case of sciatic nerve motor and sensory deficit in a 52-year-old patient 2 years after index left THA. Electromyography (EMG) results and imaging with radiographs and CT of the affected hip demonstrated an aberrant acetabular cup screw in the posterior-inferior quadrant adjacent to the sciatic nerve. Case Description  The patient underwent surgical exploration that revealed injury to the peroneal division of the sciatic nerve due to direct injury from screw impingement. A literature review identified 11 patients with late-onset neuropathy after THA. Ten patients underwent surgical exploration and pain often resolved after surgery with 56% of patients recovering sensory function and 25% experiencing full recovery of motor function. Conclusions  Delayed neuropathy of the sciatic nerve is a rare complication after THA that is most often due to hardware irritation, component failure, or wear-related pseudotumor formation. Operative intervention is often pursued to explore and directly visualize the nerve with limited results in the literature showing modest relief of pain and sensory symptoms and poor restoration of motor function.

  10. Curcumin promotes nerve regeneration and functional recovery after sciatic nerve crush injury in diabetic rats.

    PubMed

    Ma, Junxiong; Yu, Hailong; Liu, Jun; Chen, Yu; Wang, Qi; Xiang, Liangbi

    2016-01-01

    Curcumin is capable of promoting peripheral nerve regeneration in normal condition. However, it is unclear whether its beneficial effect on nerve regeneration still exists under diabetic mellitus. The present study was designed to investigate such a possibility. Diabetes in rats was developed by a single dose of streptozotocin at 50 mg/kg. Immediately after nerve crush injury, the diabetic rats were intraperitoneally administrated daily for 4 weeks with curcumin (50 mg/kg, 100 mg/kg and 300 mg/kg), or normal saline, respectively. The axonal regeneration was investigated by morphometric analysis and retrograde labeling. The functional recovery was evaluated by electrophysiological studies and behavioral analysis. Axonal regeneration and functional recovery was significantly enhanced by curcumin, which were significantly better than those in vehicle saline group. In addition, high doses of curcumin (100 mg/kg and 300 mg/kg) achieved better axonal regeneration and functional recovery than low dose (50 mg/kg). In conclusion, curcumin is capable of promoting nerve regeneration after sciatic nerve crush injury in diabetes mellitus, highlighting its therapeutic values as a neuroprotective agent for peripheral nerve injury repair in diabetes mellitus.

  11. Neuroprotective effects of ultrasound-guided nerve growth factor injections after sciatic nerve injury

    PubMed Central

    Li, Hong-fei; Wang, Yi-ru; Huo, Hui-ping; Wang, Yue-xiang; Tang, Jie

    2015-01-01

    Nerve growth factor (NGF) plays an important role in promoting neuroregeneration after peripheral nerve injury. However, its effects are limited by its short half-life; it is therefore important to identify an effective mode of administration. High-frequency ultrasound (HFU) is increasingly used in the clinic for high-resolution visualization of tissues, and has been proposed as a method for identifying and evaluating peripheral nerve damage after injury. In addition, HFU is widely used for guiding needle placement when administering drugs to a specific site. We hypothesized that HFU guiding would optimize the neuroprotective effects of NGF on sciatic nerve injury in the rabbit. We performed behavioral, ultrasound, electrophysiological, histological, and immunohistochemical evaluation of HFU-guided NGF injections administered immediately after injury, or 14 days later, and compared this mode of administration with intramuscular NGF injections. Across all assessments, HFU-guided NGF injections gave consistently better outcomes than intramuscular NGF injections administered immediately or 14 days after injury, with immediate treatment also yielding better structural and functional results than when the treatment was delayed by 14 days. Our findings indicate that NGF should be administered as early as possible after peripheral nerve injury, and highlight the striking neuroprotective effects of HFU-guided NGF injections on peripheral nerve injury compared with intramuscular administration. PMID:26807123

  12. Viscoelasticity of repaired sciatic nerve by poly(lactic-co-glycolic acid) tubes

    PubMed Central

    Piao, Chengdong; Li, Peng; Liu, Guangyao; Yang, Kun

    2013-01-01

    Medical-grade synthetic poly(lactic-co-glycolic acid) polymer can be used as a biomaterial for nerve repair because of its good biocompatibility, biodegradability and adjustable degradation rate. The stress relaxation and creep properties of peripheral nerve can be greatly improved by repair with poly(lactic-co-glycolic acid) tubes. Ten sciatic nerve specimens were harvested from fresh corpses within 24 hours of death, and were prepared into sciatic nerve injury models by creating a 10 mm defect in each specimen. Defects were repaired by anastomosis with nerve autografts and poly(lactic-co-glycolic acid) tubes. Stress relaxation and creep testing showed that at 7 200 seconds, the sciatic nerve anastomosed by poly(lactic-co-glycolic acid) tubes exhibited a greater decrease in stress and increase in strain than those anastomosed by nerve autografts. These findings suggest that poly(lactic-co-glycolic acid) exhibits good viscoelasticity to meet the biomechanical require-ments for a biomaterial used to repair sciatic nerve injury. PMID:25206634

  13. Viscoelasticity of repaired sciatic nerve by poly(lactic-co-glycolic acid) tubes.

    PubMed

    Piao, Chengdong; Li, Peng; Liu, Guangyao; Yang, Kun

    2013-11-25

    Medical-grade synthetic poly(lactic-co-glycolic acid) polymer can be used as a biomaterial for nerve repair because of its good biocompatibility, biodegradability and adjustable degradation rate. The stress relaxation and creep properties of peripheral nerve can be greatly improved by repair with poly(lactic-co-glycolic acid) tubes. Ten sciatic nerve specimens were harvested from fresh corpses within 24 hours of death, and were prepared into sciatic nerve injury models by creating a 10 mm defect in each specimen. Defects were repaired by anastomosis with nerve autografts and poly(lactic-co-glycolic acid) tubes. Stress relaxation and creep testing showed that at 7 200 seconds, the sciatic nerve anastomosed by poly(lactic-co-glycolic acid) tubes exhibited a greater decrease in stress and increase in strain than those anastomosed by nerve autografts. These findings suggest that poly(lactic-co-glycolic acid) exhibits good viscoelasticity to meet the biomechanical require-ments for a biomaterial used to repair sciatic nerve injury.

  14. Acellular allogeneic nerve grafting combined with bone marrow mesenchymal stem cell transplantation for the repair of long-segment sciatic nerve defects: biomechanics and validation of mathematical models

    PubMed Central

    Li, Ya-jun; Zhao, Bao-lin; Lv, Hao-ze; Qin, Zhi-gang; Luo, Min

    2016-01-01

    We hypothesized that a chemically extracted acellular allogeneic nerve graft used in combination with bone marrow mesenchymal stem cell transplantation would be an effective treatment for long-segment sciatic nerve defects. To test this, we established rabbit models of 30 mm sciatic nerve defects, and treated them using either an autograft or a chemically decellularized allogeneic nerve graft with or without simultaneous transplantation of bone marrow mesenchymal stem cells. We compared the tensile properties, electrophysiological function and morphology of the damaged nerve in each group. Sciatic nerves repaired by the allogeneic nerve graft combined with stem cell transplantation showed better recovery than those repaired by the acellular allogeneic nerve graft alone, and produced similar results to those observed with the autograft. These findings confirm that a chemically extracted acellular allogeneic nerve graft combined with transplantation of bone marrow mesenchymal stem cells is an effective method of repairing long-segment sciatic nerve defects. PMID:27651781

  15. Acellular allogeneic nerve grafting combined with bone marrow mesenchymal stem cell transplantation for the repair of long-segment sciatic nerve defects: biomechanics and validation of mathematical models

    PubMed Central

    Li, Ya-jun; Zhao, Bao-lin; Lv, Hao-ze; Qin, Zhi-gang; Luo, Min

    2016-01-01

    We hypothesized that a chemically extracted acellular allogeneic nerve graft used in combination with bone marrow mesenchymal stem cell transplantation would be an effective treatment for long-segment sciatic nerve defects. To test this, we established rabbit models of 30 mm sciatic nerve defects, and treated them using either an autograft or a chemically decellularized allogeneic nerve graft with or without simultaneous transplantation of bone marrow mesenchymal stem cells. We compared the tensile properties, electrophysiological function and morphology of the damaged nerve in each group. Sciatic nerves repaired by the allogeneic nerve graft combined with stem cell transplantation showed better recovery than those repaired by the acellular allogeneic nerve graft alone, and produced similar results to those observed with the autograft. These findings confirm that a chemically extracted acellular allogeneic nerve graft combined with transplantation of bone marrow mesenchymal stem cells is an effective method of repairing long-segment sciatic nerve defects.

  16. Acrylamide administration alters protein phosphorylation and phospholipid metabolism in rat sciatic nerve

    SciTech Connect

    Berti-Mattera, L.N.; Eichberg, J.; Schrama, L.; LoPachin, R.M. )

    1990-05-01

    The effects of ACR on protein phosphorylation and phospholipid metabolism were assessed in rat sciatic nerve. After 5 days of ACR administration (50 mg/kg/day) an increase in the incorporation of 32P into phosphatidylinositol-4,5-bisphosphate, phosphatidylinositol-4-phosphate, and phosphatidylcholine was detected in proximal sciatic nerve segments. In contrast, no changes in phospholipid metabolism were observed in distal segments. After 9 days of ACR treatment when neurotoxicological symptoms were clearly apparent, a generalized increase in radiolabel uptake into phospholipids was noted exclusively in proximal nerve regions. ACR-induced increases in phospholipid metabolism were toxicologically specific since comparable administration of MBA (108 mg/kg/day X 5 or 9 days) produced only minor changes. ACR intoxication was also associated with a rise in sciatic nerve protein phosphorylation. After 9 days of ACR treatment, phosphorylation of beta-tubulin, P0, and several unidentified proteins (38 and 180 kDa) was increased in distal segments. In contrast, chronic administration of MBA caused increases in phosphorylation of beta-tubulin and the major myelin proteins of proximal nerve segments. In cell free homogenates prepared from sciatic nerves of treated and control rats, MBA caused an increase in phosphorylation of major myelin proteins similar to its effect in intact proximal nerve segments. The most striking effect observed in nerve homogenates of ACR-treated rats was a marked decrease in phosphorylation of an 80-kDa protein. Addition of ACR (1 mM) to homogenates of normal nerve had no effect on protein phosphorylation. Our results indicate that changes in the phosphorylation of phospholipids and proteins in sciatic nerve might be a component of the neurotoxic mechanism of ACR.

  17. [High resolution (3 T) magnetic resonance neurography of the sciatic nerve].

    PubMed

    Cejas, C; Aguilar, M; Falcón, L; Caneo, N; Acuña, M C

    2013-01-01

    Magnetic resonance (MR) neurography refers to a set of techniques that enable the structure of the peripheral nerves and nerve plexuses to be evaluated optimally. New two-dimensional and three-dimensional neurographic sequences, in particular in 3T scanners, achieve excellent contrast between the nerve and perineural structures. MR neurography makes it possible to distinguish between the normal fascicular pattern of the nerve and anomalies like inflammation, trauma, and tumor that can affect nerves. In this article, we describe the structure of the sciatic nerve, its characteristics on MR neurography, and the most common diseases that affect it.

  18. Decompression of the Sciatic Nerve Entrapment Caused by Post-Inflammatory Scarring

    PubMed Central

    Kim, Deog-ryeong; Jeun, Sin Soo; Lee, Sang-won

    2015-01-01

    A rare case of chronic pain of entrapment neuropathy of the sciatic nerve successfully relieved by surgical decompression is presented. A 71-year-old male suffered a chronic right buttock pain of duration of 7 years which radiating to the right distal leg and foot. His pain developed gradually over one year after underwenting drainage for the gluteal abscess seven years ago. A cramping buttock and intermittently radiating pain to his right foot on sitting, walking, and voiding did not respond to conventional treatment. An MRI suggested a post-inflammatory adhesion encroaching the proximal course of the sciatic nerve beneath the piriformis as it emerges from the sciatic notch. Upon exploration of the sciatic nerve, a fibrotic tendinous scar beneath the piriformis was found and released proximally to the sciatic notch. His chronic intractable pain was completely relieved within days after the decompression. However, thigh weakness and hypesthesia of the foot did not improve. This case suggest a need for of more prompt investigation and decompression of the chronic sciatic entrapment neuropathy which does not improve clinically or electrically over several months. PMID:25733994

  19. Feasibility Study on MR-Guided High-Intensity Focused Ultrasound Ablation of Sciatic Nerve in a Swine Model: Preliminary Results

    SciTech Connect

    Kaye, Elena A.; Gutta, Narendra Babu; Monette, Sebastien; Gulati, Amitabh Loh, Jeffrey; Srimathveeravalli, Govindarajan; Ezell, Paula C.; Erinjeri, Joseph P. Solomon, Stephen B. Maybody, Majid

    2015-08-15

    IntroductionSpastic patients often seek neurolysis, the permanent destruction of the sciatic nerve, for better pain management. MRI-guided high-intensity focused ultrasound (MRgHIFU) may serve as a noninvasive alternative to the prevailing, more intrusive techniques. This in vivo acute study is aimed at performing sciatic nerve neurolysis using a clinical MRgHIFU system.MethodsThe HIFU ablation of sciatic nerves was performed in swine (n = 5) using a HIFU system integrated with a 3 T MRI scanner. Acute lesions were confirmed using T1-weighted contrast-enhanced (CE) MRI and histopathology using hematoxylin and eosin staining. The animals were euthanized immediately following post-ablation imaging.ResultsReddening and mild thickening of the nerve and pallor of the adjacent muscle were seen in all animals. The HIFU-treated sections of the nerves displayed nuclear pyknosis of Schwann cells, vascular hyperemia, perineural edema, hyalinization of the collagenous stroma of the nerve, myelin sheet swelling, and loss of axons. Ablations were visible on CE MRI. Non-perfused volume of the lesions (5.8–64.6 cc) linearly correlated with estimated lethal thermal dose volume (4.7–34.2 cc). Skin burn adjacent to the largest ablated zone was observed in the first animal. Bilateral treatment time ranged from 55 to 138 min, and preparation time required 2 h on average.ConclusionThe acute pilot study in swine demonstrated the feasibility of a noninvasive neurolysis of the sciatic nerve using a clinical MRgHIFU system. Results revealed that acute HIFU nerve lesions were detectable on CE MRI, gross pathology, and histology.

  20. Anthropometric Study of the Piriformis Muscle and Sciatic Nerve: A Morphological Analysis in a Polish Population

    PubMed Central

    Haładaj, Robert; Pingot, Mariusz; Polguj, Michał; Wysiadecki, Grzegorz; Topol, Mirosław

    2015-01-01

    Background The aim of this study was to determine relationships between piriformis muscle (PM) and sciatic nerve (SN) with reference to sex and anatomical variations. Material/Methods Deep dissection of the gluteal region was performed on 30 randomized, formalin-fixed human lower limbs of adults of both sexes of the Polish population. Anthropometric measurements were taken and then statistically analyzed. Results The conducted research revealed that, apart from the typical structure of the piriformis muscle, the most common variation was division of the piriformis muscle into two heads, with the common peroneal nerve running between them (20%). The group with anatomical variations of the sciatic nerve course displayed greater diversity of morphometric measurement results. There was a statistically significant correlation between the lower limb length and the distance from the sciatic nerve to the greater trochanter in the male specimens. On the other hand, in the female specimens, a statistically significant correlation was observed between the lower limb length and the distance from the sciatic nerve to the ischial tuberosity. The shortest distance from the sciatic nerve to the greater trochanter measured at the level of the inferior edge of the piriformis was 21 mm, while the shortest distance to the ischial tuberosity was 63 mm. Such correlations should be taken into account during invasive medical procedures performed in the gluteal region. Conclusions It is possible to distinguish several anatomical variations of the sciatic nerve course within the deep gluteal region. The statistically significant correlations between some anthropometric measurements were only present within particular groups of male and female limbs. PMID:26629744

  1. Sciatic nerve injury repair: a visualized analysis of research fronts and development trends

    PubMed Central

    Liu, Guangyao; Jiang, Rui; Jin, Yan

    2014-01-01

    A total of 3,446 publications regarding sciatic nerve injury repair and protection indexed by Web of Science during 2000–2004 were used for a detailed analysis of temporal-spatial distribution characteristics. Reference co-citation networks of the 100 top-cited publications as per the number of total citations were created using the Web of Science database and the information visualization tool, CiteSpaceIII. The key words that showed high frequency in these publications were included for analyzing the research fronts and development trends for sciatic nerve injury repair and protection. Through word frequency trend analysis, studies on bone marrow mesenchymal stem cells, adipose-derived stem cells, and skeletal muscle-derived multipotent stem cells combined with tissue-engineered scaffold material will become the forefronts in the field of sciatic nerve injury repair and protection in the near future. PMID:25374595

  2. Relationship Between the Superior Gluteal Vessels and Nerve at the Greater Sciatic Notch.

    PubMed

    Collinge, Cory A; Ziran, Navid M; Coons, David A

    2015-10-01

    Bleeding from the superior gluteal (SG) blood vessels at the greater sciatic notch is frequently encountered during acetabular fracture surgery. The purpose of this study is to define the positional anatomy of the superior gluteal vessels and nerve (SGVAN) at the greater sciatic notch. Twenty-three hemipelvi were dissected in whole human cadavers. The greater sciatic notch and SGVAN were visualized via a posterior surgical approach, identified deep in the greater sciatic notch, and traced superficially. Branches of the SGVAN and their anatomical relationship to each other were recorded. In the notch, SG arteries comprised a single vessel in 18 (78%) of 23 specimens, with all of these dividing at varying distances (1-3.5 cm) along the lateral ilium after dividing into superior and inferior branches. The SG artery branches were contiguous with periosteum of the bony notch in all specimens. More than 1 SG nerve branch was seen in the greater sciatic notch of all specimens, including an inferior branch that exited caudal or caudal-superficial to the SG vessels. The caudal-most SG nerve branch was directly adjacent to the bony notch's periosteum in 15 (65%) of 23 specimens. The SGVAN are at risk in patients undergoing acetabular fracture surgery. Individuals performing surgery along the acetabulum's posterior column would expect to encounter a major SG nerve branch (deep inferior) before encountering the SG vessels in all cases. Iatrogenic injuries to the SGVAN might be prevented by avoiding use of cautery in this area if hemorrhage is encountered.

  3. Celecoxib accelerates functional recovery after sciatic nerve crush in the rat

    PubMed Central

    2008-01-01

    The inflammatory response appears to be essential in the modulation of the degeneration and regeneration process after peripheral nerve injury. In injured nerves, cyclooxygenase-2 (COX-2) is strongly upregulated around the injury site, possibly playing a role in the regulation of the inflammatory response. In this study we investigated the effect of celecoxib, a COX-2 inhibitor, on functional recovery after sciatic nerve crush in rats. Unilateral sciatic nerve crush injury was performed on 10 male Wistar rats. Animals on the experimental group (n = 5) received celecoxib (10 mg/kg ip) immediately before the crush injury and daily for 7 days after the injury. Control group (n = 5) received normal saline at equal regimen. A sham group (n = 5), where sciatic nerve was exposed but not crushed, was also evaluated. Functional recovery was then assessed by calculating the sciatic functional index (SFI) on days 0,1,7,14 and 21 in all groups, and registering the day of motor and walking onset. In comparison with control group, celecoxib treatment (experimental group) had significant beneficial effects on SFI, with a significantly better score on day 7. Anti-inflammatory drug celecoxib should be considered in the treatment of peripheral nerve injuries, but further studies are needed to explain the mechanism of its neuroprotective effects. PMID:19036161

  4. MRI shows increased sciatic nerve cross sectional area in inherited and inflammatory neuropathies.

    PubMed

    Sinclair, C D J; Miranda, M A; Cowley, P; Morrow, J M; Davagnanam, I; Mehta, H; Hanna, M G; Koltzenburg, M; Reilly, M M; Yousry, T A; Thornton, J S

    2011-11-01

    Measurements of the cross sectional area of the sciatic nerve are described in a group of 10 patients with genetically confirmed Charcot-Marie-Tooth disease type 1A (CMT1A), nine patients with chronic inflammatory demyelinating polyneuropathy (CIDP) and 10 healthy controls using MRI. One mid-thigh of each individual was imaged using a short tau inversion recovery sequence and the nerve appearance evaluated radiologically with respect to the signal intensity and visibility of the internal neural structure. The cross sectional area of the sciatic nerve of each individual was measured by defining irregular enclosing regions of interest on the MRI images. The sciatic nerve area was enlarged in both CMT1A (p<0.001) and CIDP (p=0.008) compared with controls and in CMT1A compared with CIDP (p<0.001). Median (interquartile range) areas were 67.6 (16.2) mm(2) for the CIDP group, 135.9 (46.5) mm(2) for the CMT1A group and 43.3 (19.9) mm(2) for the control group. The critical upper value for discriminating pathologically enlarged nerves from normal controls with p<0.05 was 64.4 mm(2). Quantification of sciatic nerve hypertrophy on MRI may be of assistance in cases where the diagnosis is still in doubt, providing an objective pathological marker complimenting other clinical investigations.

  5. Postoperative sciatic and femoral or saphenous nerve blockade for lower extremity surgery in anesthetized adults

    PubMed Central

    Lollo, Loreto; Bhananker, Sanjay; Stogicza, Agnes

    2015-01-01

    Background: Guidelines warn of increased risks of injury when placing regional nerve blocks in the anesthetized adult but complications occurred in patients that received neither sedation nor local anesthetic. This restriction of nerve block administration places vulnerable categories of patients at risk of severe opioid induced side effects. Patient and operative technical factors can preclude use of preoperative regional anesthesia. The purpose of this study was to assess complications following sciatic popliteal and femoral or saphenous nerve blockade administered to anesthetized adult patients following foot and ankle surgery. Materials and Methods: Postoperative patients administered general anesthesia received popliteal sciatic nerve blockade and either femoral or saphenous nerve blockade if operative procedures included medial incisions. Nerve blocks were placed with nerve stimulator or ultrasound guidance. A continuous nerve catheter was inserted if hospital admission was over 24 hours. Opioid analgesic supplementation was administered for inadequate pain relief. Postoperative pain scores and total analgesic requirements for 24 hours were recorded. Nerve block related complications were monitored for during the hospital admission and at follow up surgical clinic evaluation. Results: 190 anesthetized adult patients were administered 357 nerve blocks. No major nerve injury or deficit was reported. One patient had numbness in the toes not ascribed to a specific nerve of the lower extremity. Perioperative opioid dose differences were noted between male and female and between opioid naïve and tolerant patients. PMID:26807391

  6. A new analgesic method, two-minute sciatic nerve press, for immediate pain relief: a randomized trial

    PubMed Central

    He, Jiman; Wu, Bin; Jiang, Xianrong; Zhang, Fenglin; Zhao, Tao; Zhang, Wenlon

    2008-01-01

    Background Current analgesics have drawbacks such as delays in acquisition, lag-times for effect, and side effects. We recently presented a preliminary report of a new analgesic method involving a two-minute sciatic nerve press, which resulted in immediate short-term relief of pain associated with dental and renal diseases. The present study investigated whether this technique was effective for pain associated with other disease types, and whether the relief was effective for up to one hour. Methods This randomized, placebo-controlled, parallel-group trial was conducted in four hospitals in Anhui Province, China. Patients with pain were sequentially recruited by participating physicians during clinic visits, and 135 patients aged 15 – 80 years were enrolled. Dental disease patients included those with acute pulpitis and periapical abscesses. Renal disease patients included those with kidney infections and/or stones. Tumor patients included those with nose, breast, stomach and liver cancers, while Emergency Room patients had various pathologies. Patients were randomly assigned to receive a "sciatic nerve press" in which pressure was applied simultaneously to the sciatic nerves at the back of both thighs, or a "placebo press" in which pressure was applied to a parallel region on the front of the thighs. Each fist applied a pressure of 11 – 20 kg for 2 minutes. Patients rated their level of pain before and after the procedure. Results The "sciatic nerve press" produced immediate relief of pain in all patient groups. Emergency patients reported a 43.5% reduction in pain (p < 0.001). Significant pain relief for dental, renal and tumor patients lasted for 60 minutes (p < 0.001). The peak pain relief occurred at the 10 – 20th minutes, and the relief decreased 47% by the 60th minutes. Conclusion Two minutes of pressure on both sciatic nerves produced immediate significant short-term conduction analgesia. This technique is a convenient, safe and powerful method for

  7. Gait phase detection from sciatic nerve recordings in functional electrical stimulation systems for foot drop correction.

    PubMed

    Chu, Jun-Uk; Song, Kang-Il; Han, Sungmin; Lee, Soo Hyun; Kang, Ji Yoon; Hwang, Dosik; Suh, Jun-Kyo Francis; Choi, Kuiwon; Youn, Inchan

    2013-05-01

    Cutaneous afferent activities recorded by a nerve cuff electrode have been used to detect the stance phase in a functional electrical stimulation system for foot drop correction. However, the implantation procedure was difficult, as the cuff electrode had to be located on the distal branches of a multi-fascicular nerve to exclude muscle afferent and efferent activities. This paper proposes a new gait phase detection scheme that can be applied to a proximal nerve root that includes cutaneous afferent fibers as well as muscle afferent and efferent fibers. To test the feasibility of this scheme, electroneurogram (ENG) signals were measured from the rat sciatic nerve during treadmill walking at several speeds, and the signal properties of the sciatic nerve were analyzed for a comparison with kinematic data from the ankle joint. On the basis of these experiments, a wavelet packet transform was tested to define a feature vector from the sciatic ENG signals according to the gait phases. We also propose a Gaussian mixture model (GMM) classifier and investigate whether it could be used successfully to discriminate feature vectors into the stance and swing phases. In spite of no significant differences in the rectified bin-integrated values between the stance and swing phases, the sciatic ENG signals could be reliably classified using the proposed wavelet packet transform and GMM classification methods.

  8. Expression and regulation of redoxins at nociceptive signaling sites after sciatic nerve injury in mice

    PubMed Central

    Valek, Lucie; Kanngießer, Maike; Tegeder, Irmgard

    2015-01-01

    Injury of the sciatic nerve results in regulations of pro- and anti-oxidative enzymes at sites of nociceptive signaling including the injured nerve, dorsal root ganglia (DRGs), dorsal horn of the spinal cord, thalamus and somatosensory cortex (Valek et al., 2015) [1]. The present DiB paper shows immunohistochemistry of redoxins including peroxiredoxins (Prdx1–6), glutaredoxins (Glrx1, 2, 3, 5), thioredoxins (Txn1, 2) and thioredoxin reductases (Txnrd1, 2) in the DRGs, spinal cord and sciatic nerve and thalamus in naïve mice and 7 days after Spared sciatic Nerve Injury (SNI) in control mice (Hif1α-flfl) and in mice with a specific deletion of hypoxia inducible factor 1 alpha (SNS-HIF1α−/−) in DRG neurons. The sciatic nerves were immunostained for the respective redoxins and counterstained with hematoxylin. The redoxin immunoreactivity was quantified with ImageJ. For the DRGs and spinal cord the data show the quantitative assessment of the intensity of redoxin immunoreactivity transformed to rainbow pseudocolors. In addition, some redoxin examples of the ipsi and contralateral dorsal and ventral horns of the lumbar spinal cord and some redoxin examples of the thalamus are presented. PMID:26693520

  9. Sequential imaging of intraneural sciatic nerve endometriosis provides insight into symptoms of cyclical sciatica.

    PubMed

    Capek, Stepan; Amrami, Kimberly K; Howe, Benjamin M; Collins, Mark S; Sandroni, Paola; Cheville, John C; Spinner, Robert J

    2016-03-01

    Endometriosis of the nerve often remains an elusive diagnosis. We report the first case of intraneural lumbosacral plexus endometriosis with sequential imaging at different phases of the menstrual cycle: during the luteal phase and menstruation. Compared to the first examination, the examination performed during the patient's period revealed the lumbosacral plexus larger and hyperintense on T2-weighted imaging. The intraneural endometriosis cyst was also larger and showed recent hemorrhage. Additionally, this case represents another example of perineural spread of endometriosis from the uterus to the lumbosacral plexus along the autonomic nerves and then distally to the sciatic nerve and proximally to the spinal nerves.

  10. Effects of 940 nm light-emitting diode (led) on sciatic nerve regeneration in rats.

    PubMed

    Serafim, Karla Guivernau Gaudens; Ramos, Solange de Paula; de Lima, Franciele Mendes; Carandina, Marcelo; Ferrari, Osny; Dias, Ivan Frederico Lupiano; Toginho Filho, Dari de Oliveira; Siqueira, Cláudia Patrícia Cardoso Martins

    2012-01-01

    The objective of the present study was to evaluate the effect of 940 nm wavelength light emitting diode (LED) phototherapy on nerve regeneration in rats. Forty male Wistar rats weighing approximately 300 g each were divided into four groups: control (C); control submitted to LED phototherapy (CLed); Sciatic Nerve Lesion without LED phototherapy (L); Sciatic Nerve Lesion with LED phototherapy (LLed). The lesion was caused by crushing the right sciatic nerve. A dose of 4 J/cm(2) was used for ten consecutive days beginning on the first postoperative day. Groups C and L were submitted to the same procedure as the LLed group, but the equipment was turned off. The LED phototherapy with 940 nm wavelength reduced the areas of edema, the number of mononuclear cells present in the inflammatory infiltration, and increased functional recovery scores at 7, 14 and 21 days. The results suggest that the use of phototherapy at 940 nm after nerve damage improves morphofunctional recovery and nerve regeneration. PMID:21547474

  11. Effects of 940 nm light-emitting diode (led) on sciatic nerve regeneration in rats.

    PubMed

    Serafim, Karla Guivernau Gaudens; Ramos, Solange de Paula; de Lima, Franciele Mendes; Carandina, Marcelo; Ferrari, Osny; Dias, Ivan Frederico Lupiano; Toginho Filho, Dari de Oliveira; Siqueira, Cláudia Patrícia Cardoso Martins

    2012-01-01

    The objective of the present study was to evaluate the effect of 940 nm wavelength light emitting diode (LED) phototherapy on nerve regeneration in rats. Forty male Wistar rats weighing approximately 300 g each were divided into four groups: control (C); control submitted to LED phototherapy (CLed); Sciatic Nerve Lesion without LED phototherapy (L); Sciatic Nerve Lesion with LED phototherapy (LLed). The lesion was caused by crushing the right sciatic nerve. A dose of 4 J/cm(2) was used for ten consecutive days beginning on the first postoperative day. Groups C and L were submitted to the same procedure as the LLed group, but the equipment was turned off. The LED phototherapy with 940 nm wavelength reduced the areas of edema, the number of mononuclear cells present in the inflammatory infiltration, and increased functional recovery scores at 7, 14 and 21 days. The results suggest that the use of phototherapy at 940 nm after nerve damage improves morphofunctional recovery and nerve regeneration.

  12. Upregulation of α1-adrenoceptors on cutaneous nerve fibres after partial sciatic nerve ligation and in complex regional pain syndrome type II.

    PubMed

    Drummond, Peter D; Drummond, Eleanor S; Dawson, Linda F; Mitchell, Vanessa; Finch, Philip M; Vaughan, Christopher W; Phillips, Jacqueline K

    2014-03-01

    After peripheral nerve injury, nociceptive afferents acquire an abnormal excitability to adrenergic agents, possibly due to an enhanced expression of α1-adrenoceptors (α1-ARs) on these nerve fibres. To investigate this in the present study, changes in α1-AR expression on nerve fibres in the skin and sciatic nerve trunk were assessed using immunohistochemistry in an animal model of neuropathic pain involving partial ligation of the sciatic nerve. In addition, α1-AR expression on nerve fibres was examined in painful and unaffected skin of patients who developed complex regional pain syndrome (CRPS) after a peripheral nerve injury (CRPS type II). Four days after partial ligation of the sciatic nerve, α1-AR expression was greater on dermal nerve fibres that survived the injury than on dermal nerve fibres after sham surgery. This heightened α1-AR expression was observed on nonpeptidergic nociceptive afferents in the injured sciatic nerve, dermal nerve bundles, and the papillary dermis. Heightened expression of α1-AR in dermal nerve bundles after peripheral nerve injury also colocalized with neurofilament 200, a marker of myelinated nerve fibres. In each patient examined, α1-AR expression was greater on nerve fibres in skin affected by CRPS than in unaffected skin from the same patient or from pain-free controls. Together, these findings provide compelling evidence for an upregulation of α1-ARs on cutaneous nociceptive afferents after peripheral nerve injury. Activation of these receptors by circulating or locally secreted catecholamines might contribute to chronic pain in CRPS type II.

  13. Bone Marrow Mesenchymal Stem Cell and Vein Conduit on Sciatic Nerve Repair in Rats

    PubMed Central

    Seyed Foroutan, Kamal; Khodarahmi, Ali; Alavi, Hootan; Pedram, Sepehr; Baghaban Eslaminejad, Mohamad Reza; Bordbar, Sima

    2015-01-01

    Background: Peripheral nerve repair with sufficient functional recovery is an important issue in reconstructive surgery. Stem cells have attracted extensive research interest in recent years. Objectives: The purpose of this study was to compare the vein conduit technique, with and without the addition of mesenchymal stem cells in gap-less nerve injury repair in rats. Materials and Methods: In this study, 36 Wistar rats were randomly allocated to three groups: In the first group, nerve repair was performed with simple neurorrhaphy (control group), in the second group, nerve repair was done with vein conduit over site (vein conduit group) and in the third group, bone marrow stem cells were instilled into the vein conduit (stem cell group) after nerve repair with vein conduit over site. Six weeks after the intervention, the sciatic function index, electrophysiological study and histological examination were performed. Results: All animals tolerated the surgical procedures and survived well. The sciatic function index and latency were significantly improved in the vein conduit (P = 0.04 and 0.03, respectively) and stem cell group (P = 0.02 and 0.03, respectively) compared with the control group. No significant difference was observed in sciatic function and latency between the vein conduit and stem-cell groups. Moreover, histological analysis showed no significant difference in regenerative density between these two groups. Conclusions: The results of this study showed that the meticulous microsurgical nerve repair, which was performed using the vein tubulization induced significantly better sciatic nerve regeneration. However, the addition of bone marrow mesenchymal stem cell to vein conduit failed to promote any significant changes in regeneration outcome. PMID:25825699

  14. Variations of the sciatic nerve anatomy and blood supply in the gluteal region: a review of the literature.

    PubMed

    Kanawati, Andrew James

    2014-11-01

    Variations of the sciatic nerve anatomy and blood supply are complex and largely not dealt with in common anatomy texts. Variations of the sciatic nerve anatomy can be divided into the height of division of its branches, relation of the branches to the piriformis muscle, and its blood supply. These variations should be well known to any surgeon operating in this anatomical region. It is unknown whether these variations increase the risk of surgical injury and consequent morbidity. This paper will review the current knowledge regarding anatomical variations of the sciatic nerve and its blood supply.

  15. The Effect of Sildenafil on Recuperation from Sciatic Nerve Injury in Rats

    PubMed Central

    Korkmaz, Mehmet Fatih; Parlakpınar, Hakan; Ceylan, Mehmet Fethi; Ediz, Levent; Şamdancı, Emine; Kekilli, Ersoy; Sağır, Mustafa

    2016-01-01

    Background: Severe functional and anatomical defects can be detected after the peripheral nerve injury. Pharmacological approaches are preferred rather than surgical treatment in the treatment of nerve injuries. Aims: The aim of this study is to perform histopathological, functional and bone densitometry examinations of the effects of sildenafil on nerve regeneration in a rat model of peripheral nerve crush injury. Study Design: Animal experiment. Methods: The study included a total of thirty adult Sprague-Dawley rats that were divided into three groups of ten rats each. In all rats, a crush injury was created by clamping the right sciatic nerve for one minute. One day before the procedure, rats in group 1 were started on a 28-day treatment consisting of a daily dose of 20 mg/kg body weight sildenafil citrate given orally via a nasogastric tube, while the rats in group 2 were started on an every-other-day dose of 10 mg/kg body weight sildenafil citrate. Rats from group 3 were not administered any drugs. Forty-two days after the nerve damage was created, functional and histopathological examination of both sciatic nerves and bone densitometric evaluation of the extremities were conducted. Results: During the rotarod test, rats from group 3 spent the least amount of time on the rod compared to the drug treatment groups at speeds of 20 rpm, 30 rpm and 40 rpm. In addition, the duration for which each animal could stay on the rod throughout the accelerod test significantly reduced in rats from group 3 compared to rats from groups 1 and 2 in the 4-min test. For the hot-plate latency time, there were no differences among the groups in either the basal level or after sciatic nerve injury. Moreover, there was no significant difference between the groups in terms of the static sciatic index (SSI) on the 42nd day (p=0.147). The amplitude was better evaluated in group 1 compared to the other two groups (p<0.05). Under microscopic evaluation, we observed the greatest amount of

  16. Reinnervation of the Tibialis Anterior Following Sciatic Nerve Crush Injury: A Confocal Microscopic Study in Transgenic Mice

    PubMed Central

    Magill, Christina K.; Tong, Alice; Kawamura, David; Hayashi, Ayato; Hunter, Daniel A.; Parsadanian, Alexander; Mackinnon, Susan E.; Myckatyn, Terence M.

    2007-01-01

    Transgenic mice whose axons and Schwann cells express fluorescent chromophores enable new imaging techniques and augment concepts in developmental neurobiology. The utility of these tools in the study of traumatic nerve injury depends on employing nerve models that are amenable to microsurgical manipulation and gauging functional recovery. Motor recovery from sciatic nerve crush injury is studied here by evaluating motor endplates of the tibialis anterior muscle, which is innervated by the deep peroneal branch of the sciatic nerve. Following sciatic nerve crush, the deep surface of the tibialis anterior muscle is examined using whole mount confocal microscopy, and reinnervation is characterized by imaging fluorescent axons or Schwann cells (SCs). One week following sciatic crush injury, 100% of motor endplates are denervated with partial reinnervation at two weeks, hyperinnervation at three and four weeks, and restoration of a 1:1 axon to motor endplate relationship six weeks after injury. Walking track analysis reveals progressive recovery of sciatic nerve function by six weeks. SCs reveal reduced S100 expression within two weeks of denervation, correlating with regression to a more immature phenotype. Reinnervation of SCs restores S100 expression and a fully differentiated phenotype. Following denervation, there is altered morphology of circumscribed terminal Schwann cells demonstrating extensive process formation between adjacent motor endplates. The thin, uniformly innervated tibialis anterior muscle is well suited for studying motor reinnervation following sciatic nerve injury. Confocal microscopy may be performed coincident with other techniques of assessing nerve regeneration and functional recovery. PMID:17628540

  17. Electrophysiological and functional effects of shock waves on the sciatic nerve of rats.

    PubMed

    Wu, Yi-Hui; Liang, Huey-Wen; Chen, Wen-Shiang; Lai, Jin-Shin; Luh, Jer-Junn; Chong, Fok-Ching

    2008-10-01

    Extracorporeal shockwave therapy (ESWT) has been applied in lithotripsy and treatments of musculoskeletal disorders over the past decade, but its effects on peripheral nerves remain unclear. This study investigated the short-term effects of shockwaves on the sciatic nerve of rats. The nerves were surgically exposed and then stimulated with shockwaves at three intensities. We evaluated the motor nerve conduction velocity (MNCV) of treated sciatic nerves before, immediately after (day 0) and at 1, 4, 7 and 14 d after shockwave treatment. Two functional tests-the sciatic functional index and the withdrawal reflex latency-were evaluated before and at 1, 4, 7 and 14 d after shockwave application. The rats were sacrificed on days 0, 1, 4, 7 and 14 for morphologic observation. The degassed treatment group received high-intensity shockwave treatment using degassed normal saline as the contact medium, and MNCV was measured before and on days 0, 1, 4, 7 and 14. The sham group received the same procedure as the treatment groups (i.e., the surgical operation to expose the sciatic nerve) but with no shockwave treatment. The control group received no surgical operation or shockwave treatment. The results showed moderate decrease in the MNCV after shockwave treatment and damage to the myelin sheath of large-diameter myelinated fibers. The effect was largest (reduction to 60.9% of baseline MNCV) and of longest duration (7 to 14 d) in the high-intensity group. There were no significant changes in functional tests. These results indicated that direct application of shockwaves can induce reversible segmental demyelination in large-diameter fibers, with the electrophysiological changes being positively correlated with the intensity of the shockwaves.

  18. Sciatic nerve injury: a simple and subtle model for investigating many aspects of nervous system damage and recovery.

    PubMed

    Savastano, Luis E; Laurito, Sergio R; Fitt, Marcos R; Rasmussen, Jorge A; Gonzalez Polo, Virginia; Patterson, Sean I

    2014-04-30

    Sciatic nerve injury has been used for over a century to investigate the process of nerve damage, to assess the absolute and relative capacity of the central and peripheral nervous systems to recover after axotomy, and to understand the development of chronic pain in many pathologies. Here we provide a historical review of the contributions of this experimental model to our current understanding of fundamental questions in the neurosciences, and an assessment of its continuing capacity to address these and future problems. We describe the different degrees of nerve injury - neurapraxia, axonotmesis, neurotmesis - together with the consequences of selective damage to the different functional and anatomic components of this nerve. The varied techniques used to model different degrees of nerve injury and their relationship to the development of neuropathic pain states are considered. We also provide a detailed anatomical description of the sciatic nerve from the spinal cord to the peripheral branches in the leg. A standardized protocol for carrying out sciatic nerve axotomy is proposed, with guides to assist in the accurate and reliable dissection of the peripheral and central branches of the nerve. Functional, histological, and biochemical criteria for the validation of the injury are described. Thus, this paper provides a review of the principal features of sciatic nerve injury, presents detailed neuroanatomical descriptions of the rat's inferior limb and spine, compares different modes of injury, offers material for training purposes, and summarizes the immediate and longterm consequences of damage to the sciatic nerve.

  19. Sciatic nerve injury: a simple and subtle model for investigating many aspects of nervous system damage and recovery.

    PubMed

    Savastano, Luis E; Laurito, Sergio R; Fitt, Marcos R; Rasmussen, Jorge A; Gonzalez Polo, Virginia; Patterson, Sean I

    2014-04-30

    Sciatic nerve injury has been used for over a century to investigate the process of nerve damage, to assess the absolute and relative capacity of the central and peripheral nervous systems to recover after axotomy, and to understand the development of chronic pain in many pathologies. Here we provide a historical review of the contributions of this experimental model to our current understanding of fundamental questions in the neurosciences, and an assessment of its continuing capacity to address these and future problems. We describe the different degrees of nerve injury - neurapraxia, axonotmesis, neurotmesis - together with the consequences of selective damage to the different functional and anatomic components of this nerve. The varied techniques used to model different degrees of nerve injury and their relationship to the development of neuropathic pain states are considered. We also provide a detailed anatomical description of the sciatic nerve from the spinal cord to the peripheral branches in the leg. A standardized protocol for carrying out sciatic nerve axotomy is proposed, with guides to assist in the accurate and reliable dissection of the peripheral and central branches of the nerve. Functional, histological, and biochemical criteria for the validation of the injury are described. Thus, this paper provides a review of the principal features of sciatic nerve injury, presents detailed neuroanatomical descriptions of the rat's inferior limb and spine, compares different modes of injury, offers material for training purposes, and summarizes the immediate and longterm consequences of damage to the sciatic nerve. PMID:24487015

  20. In Vivo Gene Transfer to Schwann Cells in the Rodent Sciatic Nerve by Electroporation.

    PubMed

    Ino, Daisuke; Iino, Masamitsu

    2016-01-01

    The formation of the myelin sheath by Schwann cells (SCs) is essential for rapid conduction of nerve impulses along axons in the peripheral nervous system. SC-selective genetic manipulation in living animals is a powerful technique for studying the molecular and cellular mechanisms of SC myelination and demyelination in vivo. While knockout/knockin and transgenic mice are powerful tools for studying SC biology, these methods are costly and time consuming. Viral vector-mediated transgene introduction into the sciatic nerve is a simpler and less laborious method. However, viral methods have limitations, such as toxicity, transgene size constraints, and infectivity restricted to certain developmental stages. Here, we describe a new method that allows selective transfection of myelinating SCs in the rodent sciatic nerve using electroporation. By applying electric pulses to the sciatic nerve at the site of plasmid DNA injection, genes of interest can be easily silenced or overexpressed in SCs in both neonatal and more mature animals. Furthermore, this in vivo electroporation method allows for highly efficient simultaneous expression of multiple transgenes. Our novel technique should enable researchers to efficiently manipulate SC gene expression, and facilitate studies on SC development and function. PMID:27683960

  1. Gabapentin attenuates neuropathic pain and improves nerve myelination after chronic sciatic constriction in rats.

    PubMed

    Câmara, Carlos C; Araújo, Celina V; de Sousa, Kalina Kelma Oliveira; Brito, Gerly A C; Vale, Mariana L; Raposo, Ramon da Silva; Mendonça, Fabiana Evaristo; Mietto, Bruno S; Martinez, Ana Maria B; Oriá, Reinaldo B

    2015-10-21

    Gabapentin (GBP) is an anti-convulsive drug often used as analgesic to control neuropathic pain. This study aimed at evaluating oral GBP treatment (30, 60, 120 mg/kg, 60 min prior to chronic constriction of the sciatic nerve (CCSN) along 15-day treatment post-injury, 12 h/12 h) by monitoring spontaneous and induced-pain behaviors in Wistar rats on 5th and 15th days post-injury during early neuropathic events. CCSN animals receiving saline were used as controls. Another aim of this study was to evaluate GBP effects on myelin basic protein (MBP) on the 5th and 15th days post-injury and nerve morphology by transmission electron microscopy to address nerve regeneration. On the 5th and 15th days, GBP (60 mg/kg) reduced neuropathic pain behaviors (scratching and biting) in the ipsilateral paw and alleviated mechanical allodynia in comparison with the neuropathic saline group. GBP significantly increased climbing and rearing behaviors in CCSN and CCSN-free animals suggesting increased motor activity rather than sedation. We found three-fold significant increase in MBP expression by western blots on the 15th day when compared to controls. In addition, GPB (60 mg/kg) improved nerve axonal, fiber and myelin area 15 days post-surgery. In conclusion, GBP alleviated mechanical and thermal allodynia and spontaneous pain-related behaviors and improved later nerve morphology. Our findings suggest that GBP improve nerve remyelination after chronic constriction of the sciatic nerve.

  2. US-Guided Femoral and Sciatic Nerve Blocks for Analgesia During Endovenous Laser Ablation

    SciTech Connect

    Yilmaz, Saim Ceken, Kagan; Alimoglu, Emel; Sindel, Timur

    2013-02-15

    Endovenous laser ablation may be associated with significant pain when performed under standard local tumescent anesthesia. The purpose of this study was to investigate the efficacy of femoral and sciatic nerve blocks for analgesia during endovenous ablation in patients with lower extremity venous insufficiency. During a 28-month period, ultrasound-guided femoral or sciatic nerve blocks were performed to provide analgesia during endovenous laser ablation in 506 legs and 307 patients. The femoral block (n = 402) was performed at the level of the inguinal ligament, and the sciatic block at the posterior midthigh (n = 124), by injecting a diluted lidocaine solution under ultrasound guidance. After the blocks, endovenous laser ablations and other treatments (phlebectomy or foam sclerotherapy) were performed in the standard fashion. After the procedures, a visual analogue pain scale (1-10) was used for pain assessment. After the blocks, pain scores were 0 or 1 (no pain) in 240 legs, 2 or 3 (uncomfortable) in 225 legs, and 4 or 5 (annoying) in 41 legs. Patients never experienced any pain higher than score 5. The statistical analysis revealed no significant difference between the pain scores of the right leg versus the left leg (p = 0.321) and between the pain scores after the femoral versus sciatic block (p = 0.7). Ultrasound-guided femoral and sciatic nerve blocks may provide considerable reduction of pain during endovenous laser and other treatments, such as ambulatory phlebectomy and foam sclerotherapy. They may make these procedures more comfortable for the patient and easier for the operator.

  3. Sciatic nerve regeneration in rats by a promising electrospun collagen/poly(ε-caprolactone) nerve conduit with tailored degradation rate

    PubMed Central

    2011-01-01

    Background To cope with the limitations faced by autograft acquisitions particularly for multiple nerve injuries, artificial nerve conduit has been introduced by researchers as a substitute for autologous nerve graft for the easy specification and availability for mass production. In order to best mimic the structures and components of autologous nerve, great efforts have been made to improve the designation of nerve conduits either from materials or fabrication techniques. Electrospinning is an easy and versatile technique that has recently been used to fabricate fibrous tissue-engineered scaffolds which have great similarity to the extracellular matrix on fiber structure. Results In this study we fabricated a collagen/poly(ε-caprolactone) (collagen/PCL) fibrous scaffold by electrospinning and explored its application as nerve guide substrate or conduit in vitro and in vivo. Material characterizations showed this electrospun composite material which was made of submicron fibers possessed good hydrophilicity and flexibility. In vitro study indicated electrospun collagen/PCL fibrous meshes promoted Schwann cell adhesion, elongation and proliferation. In vivo test showed electrospun collagen/PCL porous nerve conduits successfully supported nerve regeneration through an 8 mm sciatic nerve gap in adult rats, achieving similar electrophysiological and muscle reinnervation results as autografts. Although regenerated nerve fibers were still in a pre-mature stage 4 months postoperatively, the implanted collagen/PCL nerve conduits facilitated more axons regenerating through the conduit lumen and gradually degraded which well matched the nerve regeneration rate. Conclusions All the results demonstrated this collagen/PCL nerve conduit with tailored degradation rate fabricated by electrospinning could be an efficient alternative to autograft for peripheral nerve regeneration research. Due to its advantage of high surface area for cell attachment, it is believed that this

  4. Differential gene expression in proximal and distal nerve segments of rats with sciatic nerve injury during Wallerian degeneration

    PubMed Central

    Jiang, Nan; Li, Huaiqin; Sun, Yi; Yin, Dexin; Zhao, Qin; Cui, Shusen; Yao, Dengbing

    2014-01-01

    Wallerian degeneration is a subject of major interest in neuroscience. A large number of genes are differentially regulated during the distinct stages of Wallerian degeneration: transcription factor activation, immune response, myelin cell differentiation and dedifferentiation. Although gene expression responses in the distal segment of the sciatic nerve after peripheral nerve injury are known, differences in gene expression between the proximal and distal segments remain unclear. In the present study in rats, we used microarrays to analyze changes in gene expression, biological processes and signaling pathways in the proximal and distal segments of sciatic nerves undergoing Wallerian degeneration. More than 6,000 genes were differentially expressed and 20 types of expression tendencies were identified, mainly between proximal and distal segments at 7–14 days after injury. The differentially expressed genes were those involved in cell differentiation, cytokinesis, neuron differentiation, nerve development and axon regeneration. Furthermore, 11 biological processes were represented, related to responses to stimuli, cell apoptosis, inflammatory response, immune response, signal transduction, protein kinase activity, and cell proliferation. Using real-time quantitative PCR, western blot analysis and immunohistochemistry, microarray data were verified for four genes: aquaporin-4, interleukin 1 receptor-like 1, matrix metalloproteinase-12 and periaxin. Our study identifies differential gene expression in the proximal and distal segments of a nerve during Wallerian degeneration, analyzes dynamic biological changes of these genes, and provides a useful platform for the detailed study of nerve injury and repair during Wallerian degeneration. PMID:25206781

  5. Neurotoxicity of perineural vs intraneural-extrafascicular injection of liposomal bupivacaine in the porcine model of sciatic nerve block.

    PubMed

    Damjanovska, M; Cvetko, E; Hadzic, A; Seliskar, A; Plavec, T; Mis, K; Vuckovic Hasanbegovic, I; Stopar Pintaric, T

    2015-12-01

    Liposomal bupivacaine is a prolonged-release local anaesthetic, the neurotoxicity of which has not yet been determined. We used quantitative histomorphometric and immunohistochemical analyses to evaluate the neurotoxic effect of liposomal bupivacaine after perineural and intraneural (extrafascicular) injection of the sciatic nerve in pigs. In this double-blind prospective randomised trial, 4 ml liposomal bupivacaine 1.3% was injected either perineurally (n = 5) or intraneurally extrafascicularly (n = 5). Intraneural-extrafascicular injection of saline (n = 5) was used as a control. After emergence from anaesthesia, neurological examinations were conducted over two weeks. After harvesting the sciatic nerves, no changes in nerve fibre density or myelin width indicative of nerve injury were observed in any of the groups. Intraneural injections resulted in longer sensory blockade than perineural (p < 0.003) without persistent motor or sensory deficit. Sciatic nerve block with liposomal bupivacaine in pigs did not result in histological evidence of nerve injury.

  6. [Application of direct long-standing electrostimulation in consequences of the sciatic nerve injury].

    PubMed

    Tsymbaliuk, Iu V

    2013-04-01

    The results of surgical treatment of 57 patients, suffering consequences of the sciatic nerve injury, using the system for long-lasting electrostimulation "Naysi 3M", were presented. The domestically manufactured system is individual and gives possibility to conduct the direct electrostimulation procedures in the home conditions, several times a day, for a long time. Positive results, consisting of the various degree enhancement of the lower extremities movements volume and strength, the sensitivity restoration and the pain severity reduction or disappearance, were achieved in 46 (81%) patients. In inefficacy of conservative treatment and presence of indications for the operation in patients with sciatic nerve injury the long-lasting electrostimulation secures restoration of the lower extremities lost functions, the pain syndrome and the vegetative-trophic disorders regress.

  7. Berberine Ameliorates Allodynia Induced by Chronic Constriction Injury of the Sciatic Nerve in Rats.

    PubMed

    Kim, Hyun Jee

    2015-08-01

    The objective of this study was to investigate whether berberine could ameliorate allodynia induced by chronic constriction injury (CCI) of the sciatic nerve in rats. After inducement of CCI, significant increases in the number of paw lifts from a cold plate test (cold allodynia) and decreased paw withdrawal threshold in the von Frey hair stimulation test (mechanical allodynia) were observed. However, these cold and mechanical allodynia were markedly alleviated by berberine administration in a dose-dependent manner. Sciatic nerve myeloperoxidase and malondialdehyde activities were also attenuated by berberine administration. Continuous injection for 7 days induced no development of tolerance. The antiallodynic effect of 20 mg/kg berberine was comparable to that of amitriptyline 10 mg/kg. This study demonstrated that berberine could mitigate allodynia induced by CCI, a neuropathic pain model, and it suggested that the anti-inflammatory and antioxidative properties of berberine contributed to the antiallodynic effect in the CCI model.

  8. Berberine Ameliorates Allodynia Induced by Chronic Constriction Injury of the Sciatic Nerve in Rats.

    PubMed

    Kim, Hyun Jee

    2015-08-01

    The objective of this study was to investigate whether berberine could ameliorate allodynia induced by chronic constriction injury (CCI) of the sciatic nerve in rats. After inducement of CCI, significant increases in the number of paw lifts from a cold plate test (cold allodynia) and decreased paw withdrawal threshold in the von Frey hair stimulation test (mechanical allodynia) were observed. However, these cold and mechanical allodynia were markedly alleviated by berberine administration in a dose-dependent manner. Sciatic nerve myeloperoxidase and malondialdehyde activities were also attenuated by berberine administration. Continuous injection for 7 days induced no development of tolerance. The antiallodynic effect of 20 mg/kg berberine was comparable to that of amitriptyline 10 mg/kg. This study demonstrated that berberine could mitigate allodynia induced by CCI, a neuropathic pain model, and it suggested that the anti-inflammatory and antioxidative properties of berberine contributed to the antiallodynic effect in the CCI model. PMID:25674823

  9. [Morphometric analysis of the sciatic nerve and its principal branches in the pigeon (Columba livia)].

    PubMed

    Vita, G; Muglia, U; Ciriaco, E; Gugliotta, M A; Abbate, F; Laurà, R; Germanà, G P; Germanà, G

    1991-01-01

    The methodological approach used in this study is to characterize the number, the density and the diameter distribution of myelinated fibers (MFs) and unmyelinated fibers (UMFs) in sciatic nerve and its main branches of pigeon. The results have shown that the fiber composition is quite variable because in pigeon there are relatively MF with thin myelin sheaths and MF with thicker sheaths. Our data suggest that morphometric analysis could represent a helpful methodological approach to better characterize these systems.

  10. Treatment of postoperative sciatic nerve palsy after total hip arthroplasty for postoperative acetabular fracture: A case report.

    PubMed

    Kanda, Akio; Kaneko, Kazuo; Obayashi, Osamu; Mogami, Atsuhiko; Morohashi, Itaru

    2016-11-01

    Acetabular fracture is usually treated with osteosynthesis. However, in the case of an intra-articular fracture, osteosynthesis can result in arthropathy of the hip joint and poor long-term results, hence, total hip arthroplasty is required. However, in total hip arthroplasty for postoperative acetabular fracture, sciatic nerve palsy tends to develop more commonly than after primary total hip arthroplasty. This is a case report of a 57-year-old Japanese male who had internal skeletal fixation for a left acetabular fracture that had occurred 2 years earlier. One year later, he developed coxarthrosis and severe pain of the hip joint and total hip arthroplasty was performed. After the second surgery, he experienced pain along the distribution of the sciatic nerve and weakness of the muscles innervated by the peroneal nerve, indicating sciatic nerve palsy. We performed a third operation, and divided adhesions around the sciatic nerve. Postoperatively, the anterior hip joint pain and the buttocks pain when the hip was flexed were improved. Abduction of the fifth toe was also improved. However, the footdrop and sensory disturbance were not improved. A year after the third operation, sensory disturbance was slightly improved but the footdrop was not improved. We believe the sciatic nerve palsy developed when we dislocated the hip joint as the sciatic nerve was excessively extended as the hip joint flexed and internally rotated. Sciatic nerve adhesion can occur easily in total hip replacement for postoperative acetabular fracture; hence, adhesiotomy should be conducted before performing hip dislocation to prevent injury caused by nerve tension. The patient agreed that the details of this case could be submitted for publication. The work has been reported in line with the CARE criteria and cite. PMID:27672438

  11. Effects of nerve impulses on threshold of frog sciatic nerve fibres.

    PubMed Central

    Raymond, S A

    1979-01-01

    1. The firing thresholds of single myelinated fibres of frog sciatic nerves were monitored as a function of impulse activity in the fibre. The threshold was given by the number of coulombs in current pulses that excited a particular fibre half the time when delivered to the whole nerve. Threshold was tracked by a device that incrementally decreased the number of coulombs in the current pulse whenever the fibre responded and increased the pulse if it did not respond. 2. There was a pattern to the after-oscillations of threshold following activity. The fibres were briefly refractory, transiently superexcitable for about 1-1.5 sec and then entered a phase of raised threshold or 'depression' that lasted for many minutes. 3. Activity produced little change in the threshold curve during the refractory period. Strong depressions following prolonged activity prevented the threshold from returning to the base-line level within the time associated with the refractory period for the same fibre at rest. 4. After an impulse, superexcitability reached a maximum within 7-20 msec. This peak was larger as the number of impulses in a preceding burst increased and as the intervals between the impulses became briefer. Each successive impulse of a burst contributed less to the growth of superexcitability, and after the burst had 6-10 impulses additional impulses contributed nothing. 5. The depression phase was marked by the interaction between build-up, which depended on the activity rate, and recovery, which required as long as an hour or more for the threshold to be completely restored to resting level. These two mechanisms, one causing build-up and the other recovery, led to formation of dynamic equilibria. The threshold level at equilibrium increased monotonically with the activity rate. 6. The processes associated with superexcitability interact with those producing depression. In active fibres showing raised thresholds, impulses are followed by a relative superexcitability that

  12. A computational model for the stimulation of rat sciatic nerve using a transverse intrafascicular multichannel electrode.

    PubMed

    Raspopovic, Stanisa; Capogrosso, Marco; Micera, Silvestro

    2011-08-01

    Neuroprostheses based on electrical stimulation could potentially help disabled persons. They are based on neural interface that aim at creating an intimate contact with neural cells. The efficacy of neuroprostheses can be improved by increasing the selectivity of the neural interfaces used to stimulate specific subsets of cells. Selectivity is strongly influenced by interface design. Computer models can be useful for exploring the high dimensional space of design parameters with the aim to provide guidelines for the development of more efficient electrodes, with minimal animal use and optimization of manufacturing processes. The purpose of this study was to implement a realistic model of the performance of a transverse intrafascicular multichannel electrode (TIME) implanted into the rat sciatic nerve. A realistic finite element method (FEM) model was developed taking into account the anatomical and physiological features of the rat sciatic nerve. Electric potentials were calculated and interpolated voltages were applied to the model of a rat sciatic nerve axon, based on experimental biophysical data. Results indicate that high intra-fascicular and inter-fascicular selectivity values with low current levels can be achieved with TIMEs. The selectivity of TIMEs was also compared to an extraneural electrode, showing that higher selectivity with less current can be obtained. Using this model, the robustness of electrode performances for translational and rotational displacements were evaluated.

  13. Up-regulation of NF45 correlates with Schwann cell proliferation after sciatic nerve crush.

    PubMed

    Wang, Youhua; Zhou, Shiran; Xu, Hua; Yan, Shixian; Xu, Dawei; Zhang, Yi

    2015-05-01

    Nuclear factor (NF)45 (also known as interleukin enhancer-binding factor (ILF)2), is a transcription factor that interacts with NF90 to regulate gene expression. It has long been implicated in the regulation of cell proliferation. However, the role of NF45 in the process of peripheral nervous system regeneration after injury remains poorly understood. Herein, we investigated the spatiotemporal expression of NF45 in a rat sciatic nerve crush model. We detected the up-regulated expression of NF45 in Schwann cell after sciatic nerve crush. What's more, the expression of the cell proliferation marker proliferating cell nuclear antigen (PCNA) exhibited a similar tendency with that of NF45. In cell cultures, we observed increased expression of NF45 during the process of TNF-α-induced Schwann cell proliferation, whereas the protein level of p21 was down-regulated. Interference of NF45 led to enhanced expression of p21 and also impaired proliferation of Schwan cells. Taken together, our data implicated that NF45 was up-regulated in the sciatic nerve after crush, which was associated with proliferation of Schwann cell.

  14. Changes in the cholinergic system of rat sciatic nerve and skeletal muscle following suspension induced disuse

    NASA Technical Reports Server (NTRS)

    Gupta, R. C.; Misulis, K. E.; Dettbarn, W. D.

    1984-01-01

    Muscle disused induced changes in the cholinergic system of sciatic nerve, slow twitch soleus (SOL) and fast twitch extensor digitorum longus (EDL) muscle were studied in rats. Rats with hindlimbs suspended for 2 to 3 weeks showed marked elevation in the activity of choline acetyltransferase (ChAT) in sciatic nerve (38%), in SOL (108%) and in EDL (67%). Acetylcholinesterase (AChE) activity in SOL increased by 163% without changing the molecular forms pattern of 4S, 10S, 12S, and 16S. No significant changes in activity and molecular forms pattern of AChE were seen in EDL or in AChE activity of sciatic nerve. Nicotinic receptor binding of 3H-acetylcholine was increased in both muscles. When measured after 3 weeks of hindlimb suspension the normal distribution of type 1 fibers in SOL was reduced and a corresponding increase in type IIa and IIb fibers is seen. In EDL no significant change in fiber proportion is observed. Muscle activity, such as loadbearing, appears to have a greater controlling influence on the characteristics of the slow twitch SOL muscle than upon the fast twitch EDL muscle.

  15. Synergistic effects of micropatterned biodegradable conduits and Schwann cells on sciatic nerve regeneration

    NASA Astrophysics Data System (ADS)

    Rutkowski, Gregory E.; Miller, Cheryl A.; Jeftinija, Srdija; Mallapragada, Surya K.

    2004-09-01

    This paper describes a novel biodegradable conduit that provides a combination of physical, chemical and biological cues at the cellular level to facilitate peripheral nerve regeneration. The conduit consists of a porous poly(D,L-lactic acid) (PDLLA) tubular support structure with a micropatterned inner lumen. Schwann cells were pre-seeded into the lumen to provide additional trophic support. Conduits with micropatterned inner lumens pre-seeded with Schwann cells (MS) were fabricated and compared with three types of conduits used as controls: M (conduits with micropatterned inner lumens without pre-seeded Schwann cells), NS (conduits without micropatterned inner lumens pre-seeded with Schwann cells) and N (conduits without micropatterned inner lumens, without pre-seeded Schwann cells). The conduits were implanted in rats with 1 cm sciatic nerve transections and the regeneration and functional recovery were compared in the four different cases. The number or size of regenerated axons did not vary significantly among the different conduits. The time of recovery, and the sciatic function index, however, were significantly enhanced using the MS conduits, based on qualitative observations as well as quantitative measurements using walking track analysis. This demonstrates that biodegradable micropatterned conduits pre-seeded with Schwann cells that provide a combination of physical, chemical and biological guidance cues for regenerating axons at the cellular level offer a better alternative for repairing sciatic nerve transactions than conventional biodegradable conduits.

  16. High voltage pulsed current stimulation of the sciatic nerve in rats: analysis by the SFI

    PubMed Central

    Leoni, Anita Sofia Leite; Mazzer, Nilton; Guirro, Rinaldo Roberto de Jesus; Jatte, Fernanda Guadallini; Chereguini, Paulo Augusto Costa; Monte-Raso, Vanessa Vilela

    2012-01-01

    Objective To analyze the efficiency of high voltage pulsed current (HVPC) with early application in three different sites, in the regeneration of the sciatic nerve in rats submitted to crush injury, the sciatic functional index (SFI) was used to assess the functional recovery. Methods After crushing of the nerve, 57 animals were submitted to cathodal HVPC at frequency of 50Hz and voltage of 100V, 20 minutes per day, 5 days per week. The rats were divided into five groups: control group; ganglion group; ganglion + muscle group; muscle group; and sham group. The SFI was determined weekly for seven weeks, from the preoperative period to the 6th postoperative week. Results Compared with the control group, the results showed a significantly better performance of group 2 for the first 3 weeks; group 3 showed significantly better performance in the third week; and group 4 showed a significantly negative performance during the 4th and 6th weeks. Conclusion Early application of HVPC had a positive effect in the treatment of the spinal cord region and the sciatic nerve root ganglion with a dispersive electrode on the contralateral lumbar region or on the gastrocnemius. However, HVPC had a negative effect in the treatment with an active electrode on the gastrocnemius and a dispersive electrode on the contralateral thigh. Level of evidence II, Prospective comparative study. PMID:24453588

  17. Water Diffusion, T2, and Compartmentation in Frog Sciatic Nerve

    PubMed Central

    Peled, Sharon; Cory, David G.; Raymond, Stephen A.; Kirschner, Daniel A.; Jolesz, Ferenc A.

    2010-01-01

    A potential relationship between structural compartments in neural tissue and NMR parameters may increase the specificity of MRI in diagnosing diseases. Nevertheless, our understanding of MR of nerves and white matter is limited, particularly the influence of various water compartments on the MR signal is not known. In this study, components of the 1H transverse relaxation decay curve in frog peripheral nerve were correlated with the diffusion characteristics of the water in the nerve. Three T2 values were identified with nerve. Water mobility was found to be unrestricted on the timescale of 100 msec in the component of the signal with the intermediate T2 time, suggesting some contribution from the interstitial space to this T2 component. Restricted diffusion was observed in the component with the longest T2 time, supporting the assignment of at least part of the spins contributing to this component to an intracellular compartment. The observed nonexponential behavior of the diffusion attenuation curves was investigated and shown to be potentially caused by the wide range of axon sizes in the nerve. PMID:10542350

  18. Sciatic nerve regeneration through alginate with tubulation or nontubulation repair in cat.

    PubMed

    Sufan, W; Suzuki, Y; Tanihara, M; Ohnishi, K; Suzuki, K; Endo, K; Nishimura, Y

    2001-03-01

    A novel material for nerve regeneration, alginate, was employed in both tubulation and nontubulation repair of a long peripheral nerve defect injury. Twelve cats underwent severing of the right sciatic nerve to generate a 50-mm gap, which was treated by tubulation repair (n = 6) or nontubulation repair (n = 6). In the tubulation group, a nerve conduit consisting of polyglycolic acid mesh tube filled with alginate sponge was implanted into the gap and the tube was sutured to both nerve stumps. In the nontubulation group, the nerve defect was repaired by a simple interpolation of two pieces of alginate sponge without any suture. The animals in both groups exhibited similar recovery of locomotor function. Three months postoperatively, successful axonal elongation and reinnervation in both the afferent and efferent systems were detected by electrophysiological examinations. Intracellular electrical activity was also recorded, which is directly indicative of continuity of the regenerated nerve and restoration of the spinal reflex circuit. Eight months after operation, many regenerated myelinated axons with fascicular organization by perineurial cells were observed within the gap, peroneal and tibial branches were found in both groups, while no alginate residue was found within the regenerated nerves. In morphometric analysis of the axon density and diameter, there were no significant differences between the two groups. These results suggest that alginate is a potent material for promoting peripheral nerve regeneration. It can also be concluded that the nontubulation method is a possible repair approach for peripheral nerve defect injury.

  19. Cryoanalgesia. Ultrastructural study on cryolytic lesion of sciatic nerve in rat and rabbit.

    PubMed

    Fasano, V A; Peirone, S M; Zeme, S; Filippi, M; Broggi, G; de Mattei, M; Sguazzi, A

    1987-01-01

    The sciatic nerve was exposed to cryoinjury at different freezing patterns in albino rats and rabbits and the frozen nerves were serially examined with electron microscopy from the time of cryolitic lesion (--60 degrees C for 3 minutes) for up to 28 days. The cryolesion was characterized by a total degeneration of the myelin fibers, while non-myelin fibers and vessels seemed less affected. Regeneration began 8 days after cryolysis. A peculiar pattern was the absence of Schwann cells, while the basal membrane around regenerating axons remained intact. The hypothesis that the basal membrane might play a role is discussed. PMID:2823542

  20. Blockade of transient receptor potential cation channel subfamily V member 1 promotes regeneration after sciatic nerve injury

    PubMed Central

    Ren, Fei; Zhang, Hong; Qi, Chao; Gao, Mei-ling; Wang, Hong; Li, Xia-qing

    2015-01-01

    The transient receptor potential cation channel subfamily V member 1 (TRPV1) provides the sensation of pain (nociception). However, it remains unknown whether TRPV1 is activated after peripheral nerve injury, or whether activation of TRPV1 affects neural regeneration. In the present study, we established rat models of unilateral sciatic nerve crush injury, with or without pretreatment with AMG517 (300 mg/kg), a TRPV1 antagonist, injected subcutaneously into the ipsilateral paw 60 minutes before injury. At 1 and 2 weeks after injury, we performed immunofluorescence staining of the sciatic nerve at the center of injury, at 0.3 cm proximal and distal to the injury site, and in the dorsal root ganglia. Our results showed that Wallerian degeneration occurred distal to the injury site, and neurite outgrowth and Schwann cell regeneration occurred proximal to the injury. The number of regenerating myelinated and unmyelinated nerve clusters was greater in the AMG517-pretreated rats than in the vehicle-treated group, most notably 2 weeks after injury. TRPV1 expression in the injured sciatic nerve and ipsilateral dorsal root ganglia was markedly greater than on the contralateral side. Pretreatment with AMG517 blocked this effect. These data indicate that TRPV1 is activated or overexpressed after sciatic nerve crush injury, and that blockade of TRPV1 may accelerate regeneration of the injured sciatic nerve. PMID:26487864

  1. Local Effect of Heparin Binding Neurotrophic Factor Combined With Chitosan Entubulization on Sciatic Nerve Repair in Rats

    PubMed Central

    Mehrshad, Ali; Seddighnia, Ashkan; Shadabi, Mohammadreza; Najafpour, Alireza; Mohammadi, Rahim

    2016-01-01

    Objective: To assess the effect of on sciatic nerve regeneration in animal model of rat. Methods: Seventy-five male Wistar rats were divided into five experimental groups randomly (each group containing 15 animals): Sham operation group (SHAM), autograft group (AUTO), transected control (TC), chitosan conduit (CHIT) and heparin binding neurotrophic factor treated group (CHIT/HBNF). In AUTO group a segment of sciatic nerve was transected and reimplanted reversely. In SHAM group sciatic nerve was exposed and manipulated. In transected group left sciatic nerve was transected and stumps were fixed in adjacent muscle (TC). In treatment group defect was bridged using a chitosan conduit (CHIT) filled with 10 µL HBNF (CHIT/HBNF). Each group was subdivided into four subgroups of five animals each and nerve fibers were studied in a 12-week period. Results: Behavioral, functional, biomechanical, electrophysiological and gastrocnemius muscle mass findings and morphometric indices confirmed faster recovery of regenerated axons in treatment group than in CHIT group (P=0.001). Immunohistochemical reactions to S-100 in treatment group were more positive than that in CHIT group. Conclusion: Local administration of improved functional recovery and morphometric indices of sciatic nerve. It could be considered as an effective treatment for peripheral nerve repair in practice. PMID:27331064

  2. Deficiency in monocarboxylate transporter 1 (MCT1) in mice delays regeneration of peripheral nerves following sciatic nerve crush.

    PubMed

    Morrison, Brett M; Tsingalia, Akivaga; Vidensky, Svetlana; Lee, Youngjin; Jin, Lin; Farah, Mohamed H; Lengacher, Sylvain; Magistretti, Pierre J; Pellerin, Luc; Rothstein, Jeffrey D

    2015-01-01

    Peripheral nerve regeneration following injury occurs spontaneously, but many of the processes require metabolic energy. The mechanism of energy supply to axons has not previously been determined. In the central nervous system, monocarboxylate transporter 1 (MCT1), expressed in oligodendroglia, is critical for supplying lactate or other energy metabolites to axons. In the current study, MCT1 is shown to localize within the peripheral nervous system to perineurial cells, dorsal root ganglion neurons, and Schwann cells by MCT1 immunofluorescence in wild-type mice and tdTomato fluorescence in MCT1 BAC reporter mice. To investigate whether MCT1 is necessary for peripheral nerve regeneration, sciatic nerves of MCT1 heterozygous null mice are crushed and peripheral nerve regeneration was quantified electrophysiologically and anatomically. Compound muscle action potential (CMAP) recovery is delayed from a median of 21 days in wild-type mice to greater than 38 days in MCT1 heterozygote null mice. In fact, half of the MCT1 heterozygote null mice have no recovery of CMAP at 42 days, while all of the wild-type mice recovered. In addition, muscle fibers remain 40% more atrophic and neuromuscular junctions 40% more denervated at 42 days post-crush in the MCT1 heterozygote null mice than wild-type mice. The delay in nerve regeneration is not only in motor axons, as the number of regenerated axons in the sural sensory nerve of MCT1 heterozygote null mice at 4 weeks and tibial mixed sensory and motor nerve at 3 weeks is also significantly reduced compared to wild-type mice. This delay in regeneration may be partly due to failed Schwann cell function, as there is reduced early phagocytosis of myelin debris and remyelination of axon segments. These data for the first time demonstrate that MCT1 is critical for regeneration of both sensory and motor axons in mice following sciatic nerve crush. PMID:25447940

  3. Acetyl salicylic acid locally enhances functional recovery after sciatic nerve transection in rat.

    PubMed

    Mohammadi, Rahim; Amini, Keyvan; Abdollahi-Pirbazari, Mehdi; Yousefi, Alireza

    2013-01-01

    Local effect of acetyl salicylic acid (ASA) on peripheral nerve regeneration was studied using a rat sciatic nerve transection model. Forty-five male healthy White Wistar rats were divided into three experimental groups (n = 15), randomly: Sham-operation (SHAM), control (SIL), and ASA-treated (SIL/ASA) groups. In SHAM group after anesthesia left sciatic nerve was exposed through a gluteal muscle incision and after homeostasis the muscle was sutured. In SIL group the left sciatic nerve was exposed the same way and transected proximal to tibio-peroneal bifurcation leaving a 10-mm gap. Proximal and distal stumps were each inserted into a silicone tube and filled with 10 μl phosphate buffered solution. In SIL/ASA group defect was bridged using a silicone tube filled with 10 μl acetyl salisylic acid (0.1 mg/ml). Each group was subdivided into three subgroups of five animals each and were studied 4, 8, and 12 weeks after surgery. Data were analyzed statistically by factorial analysis of variance (ANOVA) and the Bonferroni test for pair-wise comparisons. Functional study confirmed faster and better recovery of regenerated axons in SIL/ASA than in SIL group (p < 0.05). Gastrocnemius muscle mass in SIL/ASA was significantly more than in SIL group. Morphometric indices of regenerated fibers showed that the number and diameter of the myelinated fibers in SIL/ASA were significantly higher than in control group. In immuohistochemistry, location of reactions to S-100 in SIL/ASA was clearly more positive than in SIL group. Response to local treatment of ASA demonstrates that it influences and improves functional recovery of peripheral nerve regeneration.

  4. Low-Level Laser-Accelerated Peripheral Nerve Regeneration within a Reinforced Nerve Conduit across a Large Gap of the Transected Sciatic Nerve in Rats

    PubMed Central

    Shen, Chiung-Chyi; Yang, Yi-Chin; Huang, Tsung-Bin; Chan, Shiuh-Chuan; Liu, Bai-Shuan

    2013-01-01

    This study proposed a novel combination of neural regeneration techniques for the repair of damaged peripheral nerves. A biodegradable nerve conduit containing genipin-cross-linked gelatin was annexed using beta-tricalcium phosphate (TCP) ceramic particles (genipin-gelatin-TCP, GGT) to bridge the transection of a 15 mm sciatic nerve in rats. Two trigger points were irradiated transcutaneously using 660 nm of gallium-aluminum arsenide phosphide (GaAlAsP) via laser diodes for 2 min daily over 10 consecutive days. Walking track analysis showed a significant improvement in sciatic functional index (SFI) (P < 0.01) and pronounced improvement in the toe spreading ability of rats undergoing laser stimulation. Electrophysiological measurements (peak amplitude and area) illustrated by compound muscle action potential (CMAP) curves demonstrated that laser stimulation significantly improved nerve function and reduced muscular atrophy. Histomorphometric assessments revealed that laser stimulation accelerated nerve regeneration over a larger area of neural tissue, resulting in axons of greater diameter and myelin sheaths of greater thickness than that observed in rats treated with nerve conduits alone. Motor function, electrophysiological reactions, muscular reinnervation, and histomorphometric assessments all demonstrate that the proposed therapy accelerated the repair of transected peripheral nerves bridged using a GGT nerve conduit. PMID:23737818

  5. Low-Level Laser-Accelerated Peripheral Nerve Regeneration within a Reinforced Nerve Conduit across a Large Gap of the Transected Sciatic Nerve in Rats.

    PubMed

    Shen, Chiung-Chyi; Yang, Yi-Chin; Huang, Tsung-Bin; Chan, Shiuh-Chuan; Liu, Bai-Shuan

    2013-01-01

    This study proposed a novel combination of neural regeneration techniques for the repair of damaged peripheral nerves. A biodegradable nerve conduit containing genipin-cross-linked gelatin was annexed using beta-tricalcium phosphate (TCP) ceramic particles (genipin-gelatin-TCP, GGT) to bridge the transection of a 15 mm sciatic nerve in rats. Two trigger points were irradiated transcutaneously using 660 nm of gallium-aluminum arsenide phosphide (GaAlAsP) via laser diodes for 2 min daily over 10 consecutive days. Walking track analysis showed a significant improvement in sciatic functional index (SFI) (P < 0.01) and pronounced improvement in the toe spreading ability of rats undergoing laser stimulation. Electrophysiological measurements (peak amplitude and area) illustrated by compound muscle action potential (CMAP) curves demonstrated that laser stimulation significantly improved nerve function and reduced muscular atrophy. Histomorphometric assessments revealed that laser stimulation accelerated nerve regeneration over a larger area of neural tissue, resulting in axons of greater diameter and myelin sheaths of greater thickness than that observed in rats treated with nerve conduits alone. Motor function, electrophysiological reactions, muscular reinnervation, and histomorphometric assessments all demonstrate that the proposed therapy accelerated the repair of transected peripheral nerves bridged using a GGT nerve conduit. PMID:23737818

  6. Influence of age on the late retrograde effects of sciatic nerve section in the rat.

    PubMed Central

    Kerezoudi, E; King, R H; Muddle, J R; O'Neill, J A; Thomas, P K

    1995-01-01

    The influence of age on the late retrograde effects of unilateral sciatic nerve section was investigated in rats. Operations were performed on young rats aged 3 months and older rats aged 15 and 18 months, with survival times ranging from 6 to 15 months depending upon age at the time of operation. As in previous studies, axonal atrophy was found in myelinated fibres proximal to nerve transection. This was observed to be greater in animals operated upon at 3 months of age than in those in which the sciatic nerve was transected at 15 and 18 months. In the sciatic nerve, focal intramyelinic oedema was present at a low frequency on the operated side just proximal to the section at all survival times but not on the unoperated side except in 1 old animal. Its frequency increased with age both in the dorsal and ventral roots on both sides but it was not more common on the operated side. Retrograde axonal atrophy is therefore unlikely to contribute to its occurrence. In the dorsal root ganglia the main abnormality was the presence of vacuolated neurons on the operated side. Nuclear eccentricity was also observed on the operated side in young animals in a proportion of the neurons; its frequency increased with age on the normal side and there was no difference in the older animals between operated and control sides. The possibility is discussed that growth factor deprivation secondary to axotomy is implicated in these changes. If so, there are age differences in its effect in giving rise to axonal atrophy and neuronal vacuolation. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 PMID:7591983

  7. Platelet-rich plasma gel in combination with Schwann cells for repair of sciatic nerve injury.

    PubMed

    Ye, Fagang; Li, Haiyan; Qiao, Guangxi; Chen, Feng; Tao, Hao; Ji, Aiyu; Hu, Yanling

    2012-10-15

    Bone marrow mesenchymal stem cells were isolated from New Zealand white rabbits, culture-expanded and differentiated into Schwann cell-like cells. Autologous platelet-rich plasma and Schwann cell-like cells were mixed in suspension at a density of 1 × 10(6) cells/mL, prior to introduction into a poly (lactic-co-glycolic acid) conduit. Fabricated tissue-engineered nerves were implanted into rabbits to bridge 10 mm sciatic nerve defects (platelet-rich plasma group). Controls were established using fibrin as the seeding matrix for Schwann cell-like cells at identical density to construct tissue-engineered nerves (fibrin group). Twelve weeks after implantation, toluidine blue staining and scanning electron microscopy were used to demonstrate an increase in the number of regenerating nerve fibers and thickness of the myelin sheath in the platelet-rich plasma group compared with the fibrin group. Fluoro-gold retrograde labeling revealed that the number of Fluoro-gold-positive neurons in the dorsal root ganglion and the spinal cord anterior horn was greater in the platelet-rich plasma group than in the fibrin group. Electrophysiological examination confirmed that compound muscle action potential and nerve conduction velocity were superior in the platelet-rich plasma group compared with the fibrin group. These results indicate that autologous platelet-rich plasma gel can effectively serve as a seeding matrix for Schwann cell-like cells to construct tissue-engineered nerves to promote peripheral nerve regeneration. PMID:25538751

  8. Curcumin upregulates S100 expression and improves regeneration of the sciatic nerve following its complete amputation in mice.

    PubMed

    Liu, Guo-Min; Xu, Kun; Li, Juan; Luo, Yun-Gang

    2016-08-01

    The repair of peripheral nerve injury after complete amputation is difficult, and even with anastomosis, the rapid recovery of nerve function remains challenging. Curcumin, extracted from plants of the genus Curcuma, has been shown to have anti-oxidant and anti-inflammatory properties and to improve sciatic nerve crush injury in rats. Here, we determined whether curcumin had neuroprotective effects following complete peripheral nerve amputation injury. BALB/c mice underwent complete sciatic nerve amputation, followed by an immediate epineurium anastomosis. Mice were intragastrically administered curcumin at doses of 40 (high), 20 (moderate), and 10 mg/kg/d (low) for 1 week. We found that myelin in the mice of the high- and moderate-dose curcumin groups appeared with regular shape, uniform thickness, clear boundary, and little hyperplasia surrounding the myelin. High and moderate doses of curcumin markedly improved both action potential amplitude of the sciatic nerves and the conduction velocity of the corresponding motor neurons, and upregulated mRNA and protein expression of S100, a marker for Schwann cell proliferation, in L4-6 spinal cord segments. These results suggest that curcumin is effective in promoting the repair of complete sciatic nerve amputation injury and that the underlying mechanism may be associated with upregulation of S100 expression. PMID:27651779

  9. Curcumin upregulates S100 expression and improves regeneration of the sciatic nerve following its complete amputation in mice

    PubMed Central

    Liu, Guo-min; Xu, Kun; Li, Juan; Luo, Yun-gang

    2016-01-01

    The repair of peripheral nerve injury after complete amputation is difficult, and even with anastomosis, the rapid recovery of nerve function remains challenging. Curcumin, extracted from plants of the genus Curcuma, has been shown to have anti-oxidant and anti-inflammatory properties and to improve sciatic nerve crush injury in rats. Here, we determined whether curcumin had neuroprotective effects following complete peripheral nerve amputation injury. BALB/c mice underwent complete sciatic nerve amputation, followed by an immediate epineurium anastomosis. Mice were intragastrically administered curcumin at doses of 40 (high), 20 (moderate), and 10 mg/kg/d (low) for 1 week. We found that myelin in the mice of the high- and moderate-dose curcumin groups appeared with regular shape, uniform thickness, clear boundary, and little hyperplasia surrounding the myelin. High and moderate doses of curcumin markedly improved both action potential amplitude of the sciatic nerves and the conduction velocity of the corresponding motor neurons, and upregulated mRNA and protein expression of S100, a marker for Schwann cell proliferation, in L4–6 spinal cord segments. These results suggest that curcumin is effective in promoting the repair of complete sciatic nerve amputation injury and that the underlying mechanism may be associated with upregulation of S100 expression. PMID:27651779

  10. Curcumin upregulates S100 expression and improves regeneration of the sciatic nerve following its complete amputation in mice

    PubMed Central

    Liu, Guo-min; Xu, Kun; Li, Juan; Luo, Yun-gang

    2016-01-01

    The repair of peripheral nerve injury after complete amputation is difficult, and even with anastomosis, the rapid recovery of nerve function remains challenging. Curcumin, extracted from plants of the genus Curcuma, has been shown to have anti-oxidant and anti-inflammatory properties and to improve sciatic nerve crush injury in rats. Here, we determined whether curcumin had neuroprotective effects following complete peripheral nerve amputation injury. BALB/c mice underwent complete sciatic nerve amputation, followed by an immediate epineurium anastomosis. Mice were intragastrically administered curcumin at doses of 40 (high), 20 (moderate), and 10 mg/kg/d (low) for 1 week. We found that myelin in the mice of the high- and moderate-dose curcumin groups appeared with regular shape, uniform thickness, clear boundary, and little hyperplasia surrounding the myelin. High and moderate doses of curcumin markedly improved both action potential amplitude of the sciatic nerves and the conduction velocity of the corresponding motor neurons, and upregulated mRNA and protein expression of S100, a marker for Schwann cell proliferation, in L4–6 spinal cord segments. These results suggest that curcumin is effective in promoting the repair of complete sciatic nerve amputation injury and that the underlying mechanism may be associated with upregulation of S100 expression.

  11. Cerebrolysin improves sciatic nerve dysfunction in a mouse model of diabetic peripheral neuropathy.

    PubMed

    Dong, Han-Yu; Jiang, Xin-Mei; Niu, Chun-Bo; Du, Lin; Feng, Jun-Yan; Jia, Fei-Yong

    2016-01-01

    To examine the effects of Cerebrolysin on the treatment of diabetic peripheral neuropathy, we first established a mouse model of type 2 diabetes mellitus by administering a high-glucose, high-fat diet and a single intraperitoneal injection of streptozotocin. Mice defined as diabetic in this model were then treated with 1.80, 5.39 or 8.98 mL/kg of Cerebrolysin via intraperitoneal injections for 10 consecutive days. Our results demonstrated that the number, diameter and area of myelinated nerve fibers increased in the sciatic nerves of these mice after administration of Cerebrolysin. The results of several behavioral tests showed that Cerebrolysin dose-dependently increased the slope angle in the inclined plane test (indicating an improved ability to maintain body position), prolonged tail-flick latency and foot-licking time (indicating enhanced sensitivity to thermal and chemical pain, respectively, and reduced pain thresholds), and increased an index of sciatic nerve function in diabetic mice compared with those behavioral results in untreated diabetic mice. Taken together, the anatomical and functional results suggest that Cerebrolysin ameliorated peripheral neuropathy in a mouse model of type 2 diabetes mellitus.

  12. Cerebrolysin improves sciatic nerve dysfunction in a mouse model of diabetic peripheral neuropathy

    PubMed Central

    Dong, Han-yu; Jiang, Xin-mei; Niu, Chun-bo; Du, Lin; Feng, Jun-yan; Jia, Fei-yong

    2016-01-01

    To examine the effects of Cerebrolysin on the treatment of diabetic peripheral neuropathy, we first established a mouse model of type 2 diabetes mellitus by administering a high-glucose, high-fat diet and a single intraperitoneal injection of streptozotocin. Mice defined as diabetic in this model were then treated with 1.80, 5.39 or 8.98 mL/kg of Cerebrolysin via intraperitoneal injections for 10 consecutive days. Our results demonstrated that the number, diameter and area of myelinated nerve fibers increased in the sciatic nerves of these mice after administration of Cerebrolysin. The results of several behavioral tests showed that Cerebrolysin dose-dependently increased the slope angle in the inclined plane test (indicating an improved ability to maintain body position), prolonged tail-flick latency and foot-licking time (indicating enhanced sensitivity to thermal and chemical pain, respectively, and reduced pain thresholds), and increased an index of sciatic nerve function in diabetic mice compared with those behavioral results in untreated diabetic mice. Taken together, the anatomical and functional results suggest that Cerebrolysin ameliorated peripheral neuropathy in a mouse model of type 2 diabetes mellitus. PMID:26981106

  13. Cerebrolysin improves sciatic nerve dysfunction in a mouse model of diabetic peripheral neuropathy.

    PubMed

    Dong, Han-Yu; Jiang, Xin-Mei; Niu, Chun-Bo; Du, Lin; Feng, Jun-Yan; Jia, Fei-Yong

    2016-01-01

    To examine the effects of Cerebrolysin on the treatment of diabetic peripheral neuropathy, we first established a mouse model of type 2 diabetes mellitus by administering a high-glucose, high-fat diet and a single intraperitoneal injection of streptozotocin. Mice defined as diabetic in this model were then treated with 1.80, 5.39 or 8.98 mL/kg of Cerebrolysin via intraperitoneal injections for 10 consecutive days. Our results demonstrated that the number, diameter and area of myelinated nerve fibers increased in the sciatic nerves of these mice after administration of Cerebrolysin. The results of several behavioral tests showed that Cerebrolysin dose-dependently increased the slope angle in the inclined plane test (indicating an improved ability to maintain body position), prolonged tail-flick latency and foot-licking time (indicating enhanced sensitivity to thermal and chemical pain, respectively, and reduced pain thresholds), and increased an index of sciatic nerve function in diabetic mice compared with those behavioral results in untreated diabetic mice. Taken together, the anatomical and functional results suggest that Cerebrolysin ameliorated peripheral neuropathy in a mouse model of type 2 diabetes mellitus. PMID:26981106

  14. Deep gluteal syndrome: anatomy, imaging, and management of sciatic nerve entrapments in the subgluteal space.

    PubMed

    Hernando, Moisés Fernández; Cerezal, Luis; Pérez-Carro, Luis; Abascal, Faustino; Canga, Ana

    2015-07-01

    Deep gluteal syndrome (DGS) is an underdiagnosed entity characterized by pain and/or dysesthesias in the buttock area, hip or posterior thigh and/or radicular pain due to a non-discogenic sciatic nerve entrapment in the subgluteal space. Multiple pathologies have been incorporated in this all-included "piriformis syndrome," a term that has nothing to do with the presence of fibrous bands, obturator internus/gemellus syndrome, quadratus femoris/ischiofemoral pathology, hamstring conditions, gluteal disorders and orthopedic causes. The concept of fibrous bands playing a role in causing symptoms related to sciatic nerve mobility and entrapment represents a radical change in the current diagnosis of and therapeutic approach to DGS. The development of periarticular hip endoscopy has led to an understanding of the pathophysiological mechanisms underlying piriformis syndrome, which has supported its further classification. A broad spectrum of known pathologies may be located nonspecifically in the subgluteal space and can therefore also trigger DGS. These can be classified as traumatic, iatrogenic, inflammatory/infectious, vascular, gynecologic and tumors/pseudo-tumors. Because of the ever-increasing use of advanced magnetic resonance neurography (MRN) techniques and the excellent outcomes of the new endoscopic treatment, radiologists must be aware of the anatomy and pathologic conditions of this space. MR imaging is the diagnostic procedure of choice for assessing DGS and may substantially influence the management of these patients. The infiltration test not only has a high diagnostic but also a therapeutic value. This article describes the subgluteal space anatomy, reviews known and new etiologies of DGS, and assesses the role of the radiologist in the diagnosis, treatment and postoperative evaluation of sciatic nerve entrapments, with emphasis on MR imaging and endoscopic correlation.

  15. Acute and subacute effects of the ultrasonic blade and electrosurgery on nerve physiology

    PubMed Central

    Chen, Chaoyang; Kallakuri, Srinivasu; Cavanaugh, John M.; Broughton, Duan; Clymer, Jeffrey W.

    2015-01-01

    Abstract Ultrasonic blades have been shown to cause less acute electrophysiological damage when applied near nerves than monopolar electrosurgery (ES). This study was performed to determine whether the acute nerve damage observed for ES, as well as the relative lack of damage observed for ultrasonic dissection, extends through a subacute timeframe. Muscle incisions were made in rat with the Harmonic® Blade (HB) and ES at a distance of 2 mm from the sciatic nerve. Sham surgery was also performed which consisted of similar exposure of the sciatic nerve without use of an energized device. Electrophysiological function was assessed acutely over a 3-h period, and subacutely after a 7-day survival, by monitoring the sciatic nerve compound action potential (CAP), conduction velocity (CV), von Frey hair (VFH) stimulation force, leukocyte infiltration, and impaired axonal transport via β-amyloid precursor protein (β-APP) immunocytochemistry. During the acute period, ES produced significantly lower CAP and CV, and higher levels of leukocytes and β-APP than sham, whereas the ultrasonic blade was not significantly different from sham, and had significantly lower VFH force than ES. After the subacute survival, ES continued to display significantly lower CAP and CV, and higher levels of leukocytes and β-APP than sham, whereas ultrasonic blade had higher CAP and CV than sham, and lower VFH than ES. This study confirms that incisions made with an ultrasonic blade cause less acute nerve damage than monopolar ES, and are comparable to sham surgery at a distance of 2 mm from the sciatic nerve. The negative effects of electrosurgery extend through at least a 7-day survival period, whereas subacute recovery after application of the ultrasonic blade was comparable to that of sham surgery. For surgical procedures in the vicinity of vital nerves, use of the ultrasonic blade represents a lower risk than ES for both acute and subacute neural trauma. PMID:25812024

  16. Epidermal laser stimulation of action potentials in the frog sciatic nerve

    NASA Astrophysics Data System (ADS)

    Jindra, Nichole M.; Goddard, Douglas; Imholte, Michelle; Thomas, Robert J.

    2010-01-01

    Measurements of laser-stimulated action potentials in the sciatic nerve of leopard frogs (Rana pipiens) are made using two infrared lasers. The dorsal sides of the frog's hind limbs are exposed to short-pulsed 1540- and 1064-nm wavelengths at three separate spot sizes: 2, 3, and 4 mm. Energy density thresholds are determined for eliciting an action potential at each experimental condition. Results from these exposures show similar evoked potential thresholds for both wavelengths. The 2-mm-diam spot sizes yield action potentials at radiant exposure levels almost double that seen with larger beam sizes.

  17. Crosstalk between p38, Hsp25 and Akt in spinal motor neurons after sciatic nerve injury

    NASA Technical Reports Server (NTRS)

    Murashov, A. K.; Ul Haq, I.; Hill, C.; Park, E.; Smith, M.; Wang, X.; Wang, X.; Goldberg, D. J.; Wolgemuth, D. J.

    2001-01-01

    The p38 stress-activated protein kinase pathway is involved in regulation of phosphorylation of Hsp25, which in turn regulates actin filament dynamic in non-neuronal cells. We report that p38, Hsp25 and Akt signaling pathways were specifically activated in spinal motor neurons after sciatic nerve axotomy. The activation of the p38 kinase was required for induction of Hsp25 expression. Furthermore, Hsp25 formed a complex with Akt, a member of PI-3 kinase pathway that prevents neuronal cell death. Together, our observations implicate Hsp25 as a central player in a complex system of signaling that may both promote regeneration of nerve fibers and prevent neuronal cell death in the injured spinal cord.

  18. Repeatability of measuring sciatic nerve excursion during a modified passive straight leg raise test with ultrasound imaging.

    PubMed

    Ridehalgh, Colette; Moore, Ann; Hough, Alan

    2012-12-01

    The purpose of this study was to establish the reliability of a frame-by-frame cross correlation method of assessing longitudinal sciatic nerve excursion motion using real time ultrasound imaging during a modified passive straight leg raise (SLR) test. Eighteen asymptomatic participants (age range 19-68 years) lay on their sides on a purpose made jig and the sciatic nerve in the posterior thigh was imaged during knee extension at 30° and then 60° of hip flexion (HF). Participants were re-tested ≥48 h later. The ultrasound images were analysed off-line using cross correlation software. Results demonstrated excellent repeatability of in vivo sciatic nerve excursion during a modified SLR (HF30° ICC 0.92, CI 0.79-0.97, SEM 0.69; HF60° ICC 0.96, CI 0.89-0.99, SEM 0.87). The authors also identify points of good practise to ensure an accurate as possible measurement of nerve excursion using this method. These include breaking down larger movements into sub-components, visually tracking the moving nerve during the tracking procedure, and ensuring the optimal image is captured prior to analysis. The use of ultrasound imaging in lower limb nerve dysfunction will enhance the understanding of how nerves move in vivo during neurodynamic testing, as well as being able to identify possible alteration to nerve movements in patients with neuropathic pain states.

  19. An immunohistochemical study of the sciatic nerve in a rat knee immobilization model

    PubMed Central

    Yoshida, Shinya; Matsuzaki, Taro; Hoso, Masahiro

    2016-01-01

    [Purpose] This study was performed to immunohistochemically evaluate changes in the periphery of the sciatic nerve in a rat model of knee immobilization, and to assess the effects of range of motion exercise. [Subjects and Methods] Twenty-one male rats were divided randomly into three groups: control (C), immobilized (I), and exercise (E group). Rats in the I and E groups had the right knee joint immobilized for 2 weeks. In the E group, range of motion exercise was also performed. After the experimental period, the periphery of the sciatic nerve was immunohistochemically observed. [Results] Immunohistochemical staining revealed that the myelin sheath and the perineurium in all groups were laminin positive. In the C and E groups, all rats showed normal staining. In contrast, 4 rats in the I group exhibited weak labeling. [Conclusion] Our results suggest that immobilization alters the perineurium at a molecular level and the range of motion exercise is essential for maintaining the environment of the perineurium. PMID:27190437

  20. Sciatic nerve transection modulates oxidative parameters in spinal and supraspinal regions.

    PubMed

    Scheid, Taína; Bosco, Lidiane Dal; Guedes, Renata P; Pavanato, Maria Amália; Belló-Klein, Adriane; Partata, Wania A

    2013-05-01

    Neuropathic pain is a very common dysfunction caused by several types of nerve injury. This condition leads to a variety of pathological changes in central nervous system regions related to pain transmission. It has been demonstrated that nociception is modulated by reactive oxidative species and treatments with antioxidant compounds produce antinociceptive effects. Thus, the aim of the present study was to investigate oxidative parameters in spinal and supraspinal regions following sciatic nerve transection (SNT). In behavioral assessments, animals showed mechanical allodynia and a significant functional impairment following SNT, measured by von Frey hairs test and sciatic functional index, respectively. Superoxide dismutase activity was increased 3 and 7 days following SNT in cerebral cortex and brainstem. Catalase activity was also increased in cerebral cortex 3 days after SNT. Ascorbic acid levels were decreased 7 days in the spinal cord only in SNT group. We also showed an increase in lipid peroxidation in cerebral cortex and brainstem 3 days after surgery in SNT and sham groups. These results showed that supraspinal regions also exhibit changes in antioxidant activity after SNT and demonstrate an intricate relationship among antioxidant defenses in different regions of the neuro axis related to pain transmission. PMID:23423532

  1. Motor nerve conduction velocity (MCV) and lead content in sciatic nerve of lead-exposed rats

    SciTech Connect

    Maehara, N.; Uchino, E.; Terayama, K.; Ohno, H.; Yamamura, K.

    1986-07-01

    There have been many pathological and electrophysiological studies of peripheral nerves in inorganic lead intoxication. Peripheral nerve conduction velocity (NCV) has been used as an objective measure of the effects of lead on the peripheral nerve function and has been examined with blood lead content. There have been few reports on the changes in NCV related to lead content in the peripheral nerve tissue under lead poisoning. In the present study, the authors have examined motor nerve conduction velocity (MCV) of the tail by a non-invasive method and lead content of the peripheral nerve in lead-exposed rats. Furthermore, they have attempted to assess the relationship between these two parameters.

  2. The influence of bacterial collagenase on regeneration of severed rat sciatic nerves.

    PubMed

    Wehling, P; Pak, M; Cleveland, S; Nieper, R

    1992-01-01

    Regeneration of peripheral nerve fibers is impeded by the formation of scar tissue at the site of injury. The possible beneficial effect of collagenase on nerve regeneration was studied using clinical, neurophysiological (evoked potentials) and histological (nerve fiber counts) methods. The sciatic nerves of rats were transected and the severed ends abutted and sewn together. In one series, the area about the lesion was covered with fibrin adhesive and infused with either isotonic saline (controls) or collagenase (treatment group). In the other series, the severed ends of the nerve were inserted into a silicone tube and separated by a collagen plug, which was infused with either saline or collagenase. Compared to the controls, the treated animals showed a significant improvement of clinical and neurophysiological parameters. After 3 months of observation, the collagen content of the transection site was reduced, and in the silicone series, the total number of myelinated axons 5 mm distal to the site of transection was increased, while the fiber diameter distribution was unchanged. PMID:1336302

  3. Inhibition by TRPA1 agonists of compound action potentials in the frog sciatic nerve

    SciTech Connect

    Matsushita, Akitomo; Ohtsubo, Sena; Fujita, Tsugumi; Kumamoto, Eiichi

    2013-04-26

    Highlights: •TRPA1 agonists inhibited compound action potentials in frog sciatic nerves. •This inhibition was not mediated by TRPA1 channels. •This efficacy was comparable to those of lidocaine and cocaine. •We found for the first time an ability of TRPA1 agonists to inhibit nerve conduction. -- Abstract: Although TRPV1 and TRPM8 agonists (vanilloid capsaicin and menthol, respectively) at high concentrations inhibit action potential conduction, it remains to be unknown whether TRPA1 agonists have a similar action. The present study examined the actions of TRPA1 agonists, cinnamaldehyde (CA) and allyl isothiocyanate (AITC), which differ in chemical structure from each other, on compound action potentials (CAPs) recorded from the frog sciatic nerve by using the air-gap method. CA and AITC concentration-dependently reduced the peak amplitude of the CAP with the IC{sub 50} values of 1.2 and 1.5 mM, respectively; these activities were resistant to a non-selective TRP antagonist ruthenium red or a selective TRPA1 antagonist HC-030031. The CA and AITC actions were distinct in property; the latter but not former action was delayed in onset and partially reversible, and CA but not AITC increased thresholds to elicit CAPs. A CAP inhibition was seen by hydroxy-α-sanshool (by 60% at 0.05 mM), which activates both TRPA1 and TRPV1 channels, a non-vanilloid TRPV1 agonist piperine (by 20% at 0.07 mM) and tetrahydrolavandulol (where the six-membered ring of menthol is opened; IC{sub 50} = 0.38 mM). It is suggested that TRPA1 agonists as well as TRPV1 and TRPM8 agonists have an ability to inhibit nerve conduction without TRP activation, although their agonists are quite different in chemical structure from each other.

  4. Release of axonally transported material from an in vitro amphibian sciatic nerve preparation

    SciTech Connect

    Snyder, R.E.

    1988-04-01

    The rapid axonal transport of a pulse of (35S)methionine-labelled material was used to study the release of transported material from amphibian nerve maintained in vitro. Following creation of a moving pulse of activity in a dorsal root ganglion-sciatic nerve preparation, the ganglion was removed and the nerve placed in a three-compartment tray, the section of nerve in the middle compartment containing no truncated branches (unbranched section). All three compartments were filled with a saline solution that in some studies contained nonradioactive methionine (1.0 mmol/L). Analysis of studies in which nonradioactive methionine was absent revealed that labelled material appeared in the bathing solution of the end compartments that contained truncated branches, but not in the solution of the middle (unbranched) compartment. The quantity of label released in the branched compartments was approximately 6% of that remaining in the corresponding section of nerve following an 18-20 h incubation period. However, when nonradioactive methionine was present, all compartments showed an additional activity in the bathing solution of approximately 10% of that remaining in the nerve. In another study in which a position-sensitive detector of ionizing radiation was used to monitor progress of the pulse, it was found that activity did not enter the bathing solution of a compartment prior to the pulse of activity. It is concluded that in the absence of methionine from the bathing solution, axonally transported material is released only from regions of nerve that contain severed axons; however, the presence of methionine allows transported material to be released from nerve containing intact axons. Ultrafiltration studies and thin-layer chromatography revealed the majority of material released to be of low-molecular weight (less than 30,000 daltons) and not free (35S)methionine.

  5. Effect of local administration of platelet-derived growth factor B on functional recovery of peripheral nerve regeneration: A sciatic nerve transection model

    PubMed Central

    Golzadeh, Atefeh; Mohammadi, Rahim

    2016-01-01

    Background: Effects of platelet-derived growth factor B (PDGF-B) on peripheral nerve regeneration was studied using a rat sciatic nerve transection model. Materials and Methods: Forty-five male, white Wistar rats were divided into three experimental groups (n = 15), randomly: Normal control group (NC), silicon group (SIL), and PDGF-B treated group (SIL/PDGF). In NC group, left sciatic nerve was exposed through a gluteal muscle incision and after homeostasis muscle was sutured. In the SIL group, the left sciatic nerve was exposed in the same way and transected proximal to tibio-peroneal bifurcation leaving a 10-mm gap. Proximal and distal stumps were each inserted into a silicone conduit and filled with 10 μL phosphate buffered solution. In SIL/PDGF group, the silicon conduit was filled with 10 μL PDGF-B (0.5 ng/mL). Each group was subdivided into three subgroups of five and were studied in 4, 8, 12 weeks after surgery. Results: Behavioral testing, sciatic nerve functional study, gastrocnemius muscle mass, and histomorphometric studies showed earlier regeneration of axons in SIL/PDGF than in SIL group (P < 0.05). Conclusion: Local administration of PDGF-B combined with silicon grafting could accelerate functional recovery and may have clinical implications for the surgical management of patients after facial nerve transection. PMID:27274342

  6. Rat sciatic nerve reconstruction across a 30 mm defect bridged by an oriented porous PHBV tube with Schwann cell as artificial nerve graft.

    PubMed

    Karimi, Mina; Biazar, Esmaeil; Keshel, Saeed Heidari; Ronaghi, Abdolaziz; Doostmohamadpour, Jafar; Janfada, Alireza; Montazeri, Arash

    2014-01-01

    An oriented poly(3-hydroxybutyrate-co-3-hydroxyvalerate) nerve conduit has been used to evaluate its efficiency based on the promotion of peripheral nerve regeneration in rats. The oriented porous micropatterned artificial nerve conduit was designed onto the micropatterned silicon wafers, and then their surfaces were modified with oxygen plasma to increase cell adhesion. The designed conduits were investigated by cell culture analyses with Schwann cells (SCs). The conduits were implanted into a 30 mm gap in sciatic nerves of rats. Four months after surgery, the regenerated nerves were monitored and evaluated by macroscopic assessments and histology and behavioral analyses. Results of cellular analyses showed suitable properties of designed conduit for nerve regeneration. The results demonstrated that in the polymeric graft with SCs, the rat sciatic nerve trunk had been reconstructed with restoration of nerve continuity and formatted nerve fibers with myelination. Histological results demonstrated the presence of Schwann and glial cells in regenerated nerves. Functional recovery such as walking, swimming, and recovery of nociceptive function was illustrated for all the grafts especially conduits with SCs. This study proves the feasibility of the artificial nerve graft filled with SCs for peripheral nerve regeneration by bridging a longer defect in an animal model. PMID:24399063

  7. Rat Sciatic Nerve Reconstruction Across a 30 mm Defect Bridged by an Oriented Porous PHBV Tube With Schwann Cell as Artificial Nerve Graft

    PubMed Central

    2014-01-01

    An oriented poly(3-hydroxybutyrate-co-3-hydroxyvalerate) nerve conduit has been used to evaluate its efficiency based on the promotion of peripheral nerve regeneration in rats. The oriented porous micropatterned artificial nerve conduit was designed onto the micropatterned silicon wafers, and then their surfaces were modified with oxygen plasma to increase cell adhesion. The designed conduits were investigated by cell culture analyses with Schwann cells (SCs). The conduits were implanted into a 30 mm gap in sciatic nerves of rats. Four months after surgery, the regenerated nerves were monitored and evaluated by macroscopic assessments and histology and behavioral analyses. Results of cellular analyses showed suitable properties of designed conduit for nerve regeneration. The results demonstrated that in the polymeric graft with SCs, the rat sciatic nerve trunk had been reconstructed with restoration of nerve continuity and formatted nerve fibers with myelination. Histological results demonstrated the presence of Schwann and glial cells in regenerated nerves. Functional recovery such as walking, swimming, and recovery of nociceptive function was illustrated for all the grafts especially conduits with SCs. This study proves the feasibility of the artificial nerve graft filled with SCs for peripheral nerve regeneration by bridging a longer defect in an animal model. PMID:24399063

  8. Transient Heat Hyperalgesia During Resolution of Ropivacaine Sciatic Nerve Block in the Rat

    PubMed Central

    Kolarczyk, Lavinia M.; Williams, Brian A.

    2011-01-01

    Background Preliminary studies using perineural sciatic ropivacaine in rat demonstrated unexpected heat hyperalgesia after block resolution. To better characterize the time course relative to mechanical anesthesia-analgesia, we tested the hypothesis that ropivacaine 0.5% leads to transient heat hyperalgesia in rat independent of mechanical nociception. We also evaluated functional toxicity (e.g., long-term hyperalgesia and/or tactile allodynia 2 weeks post-injection). Methods Under surgical exposure, left sciatic nerve block was performed in 2 groups of adult male rats – ropivacaine (200 μL, 5 mg/mL, n=14) versus vehicle (n=11). The efficacy and duration of block was assessed with serial heat, mechanical (Randall-Selitto testing), and tactile (von Frey-like monofilaments) tests; motor-proprioceptive (rotarod) and sedation tests were employed 1 hr and 7 hr post-injection. The presence of nerve injury was assessed by repeating the heat, tactile, and motor tests 12–14 days post-injection. Results Ropivacaine-induced anesthesia was fully manifest at 1 hr post-injection. At 3 hr post-injection, heat hypersensitivity was present in the setting of resolved mechanical analgesia. All behavioral measures returned to baseline by 2 wk post-injection. There was no evidence of (i) behavioral sedation, (ii) persistent changes in heat or mechanical sensitivity, or (iii) persistent changes in proprioceptive-motor function at 12–14 days post-injection. Conclusions Ropivacaine 0.5% induces transient heat hyperalgesia in the setting of resolved mechanical analgesia, further suggestive of modality and/or nociceptive fiber specificity. Whether this finding partially translates to “rebound pain” after patients’ nerve blocks wear off requires further study. PMID:21451438

  9. Conserved Dopamine Neurotrophic Factor-Transduced Mesenchymal Stem Cells Promote Axon Regeneration and Functional Recovery of Injured Sciatic Nerve

    PubMed Central

    Liu, Yi; Nie, Lin; Zhao, Hua; Zhang, Wen; Zhang, Yuan-Qiang; Wang, Shuai-Shuai; Cheng, Lei

    2014-01-01

    Peripheral nerve injury (PNI) is a common disease that often results in axonal degeneration and the loss of neurons, ultimately leading to limited nerve regeneration and severe functional impairment. Currently, there are no effective treatments for PNI. In the present study, we transduced conserved dopamine neurotrophic factor (CDNF) into mesenchymal stem cells (MSCs) in collagen tubes to investigate their regenerative effects on rat peripheral nerves in an in vivo transection model. Scanning electron microscopy of the collagen tubes demonstrated their ability to be resorbed in vivo. We observed notable overexpression of the CDNF protein in the distal sciatic nerve after application of CDNF-MSCs. Quantitative analysis of neurofilament 200 (NF200) and S100 immunohistochemistry showed significant enhancement of axonal and Schwann cell regeneration in the group receiving CDNF-MSCs (CDNF-MSCs group) compared with the control groups. Myelination thickness, axon diameter and the axon-to fiber diameter ratio (G-ratio) were significantly higher in the CDNF-MSCs group at 8 and 12 weeks after nerve transection surgery. After surgery, the sciatic functional index, target muscle weight, wet weight ratio of gastrocnemius muscle and horseradish peroxidase (HRP) tracing demonstrated functional recovery. Light and electron microscopy confirmed successful regeneration of the sciatic nerve. The greater numbers of HRP-labeled neuron cell bodies and increased sciatic nerve index values (SFI) in the CDNF-MSCs group suggest that CDNF exerts neuroprotective effects in vivo. We also observed higher target muscle weights and a significant improvement in muscle atrophism in the CDNF-MSCs group. Collectively, these findings indicate that CDNF gene therapy delivered by MSCs is capable of promoting nerve regeneration and functional recovery, likely because of the significant neuroprotective and neurotrophic effects of CDNF and the superior environment offered by MSCs and collagen tubes. PMID

  10. Effects of umbilical cord tissue mesenchymal stem cells (UCX®) on rat sciatic nerve regeneration after neurotmesis injuries

    PubMed Central

    Gärtner, A; Pereira, T; Armada-da-Silva, PAS; Amado, S; Veloso, AP; Amorim, I; Ribeiro, J; Santos, JD; Bárcia, RN; Cruz, P; Cruz, H; Luís, AL; Santos, JM; Geuna, S; Maurício, AC

    2014-01-01

    Peripheral nerves have the intrinsic capacity of self-regeneration after traumatic injury but the extent of the regeneration is often very poor. Increasing evidence demonstrates that mesenchymal stem/stromal cells (MSCs) may play an important role in tissue regeneration through the secretion of soluble trophic factors that enhance and assist in repair by paracrine activation of surrounding cells. In the present study, the therapeutic value of a population of umbilical cord tissue-derived MSCs, obtained by a proprietary method (UCX®), was evaluated on end-to-end rat sciatic nerve repair. Furthermore, in order to promote both, end-to-end nerve fiber contacts and MSC cell-cell interaction, as well as reduce the flush away effect of the cells after administration, a commercially available haemostatic sealant, Floseal®, was used as vehicle. Both, functional and morphologic recoveries were evaluated along the healing period using extensor postural thrust (EPT), withdrawal reflex latency (WRL), ankle kinematics analysis, and either histological analysis or stereology, in the hyper-acute, acute and chronic phases of healing. The histological analysis of the hyper-acute and acute phase studies revealed that in the group treated with UCX® alone the Wallerian degeneration was improved for the subsequent process of regeneration, the fiber organization was higher, and the extent of fibrosis was lower. The chronic phase experimental groups revealed that treatment with UCX® induced an increased number of regenerated fibers and thickening of the myelin sheet. Kinematics analysis showed that the ankle joint angle determined for untreated animals was significantly different from any of the treated groups at the instant of initial contact (IC). At opposite toe off (OT) and heel rise (HR), differences were found between untreated animals and the groups treated with either uCx® alone or UCX® administered with Floseal®. Overall, the UCX® application presented positive effects in

  11. Effects of umbilical cord tissue mesenchymal stem cells (UCX®) on rat sciatic nerve regeneration after neurotmesis injuries.

    PubMed

    Gärtner, A; Pereira, T; Armada-da-Silva, Pas; Amado, S; Veloso, Ap; Amorim, I; Ribeiro, J; Santos, Jd; Bárcia, Rn; Cruz, P; Cruz, H; Luís, Al; Santos, Jm; Geuna, S; Maurício, Ac

    2014-01-01

    Peripheral nerves have the intrinsic capacity of self-regeneration after traumatic injury but the extent of the regeneration is often very poor. Increasing evidence demonstrates that mesenchymal stem/stromal cells (MSCs) may play an important role in tissue regeneration through the secretion of soluble trophic factors that enhance and assist in repair by paracrine activation of surrounding cells. In the present study, the therapeutic value of a population of umbilical cord tissue-derived MSCs, obtained by a proprietary method (UCX(®)), was evaluated on end-to-end rat sciatic nerve repair. Furthermore, in order to promote both, end-to-end nerve fiber contacts and MSC cell-cell interaction, as well as reduce the flush away effect of the cells after administration, a commercially available haemostatic sealant, Floseal(®), was used as vehicle. Both, functional and morphologic recoveries were evaluated along the healing period using extensor postural thrust (EPT), withdrawal reflex latency (WRL), ankle kinematics analysis, and either histological analysis or stereology, in the hyper-acute, acute and chronic phases of healing. The histological analysis of the hyper-acute and acute phase studies revealed that in the group treated with UCX(®) alone the Wallerian degeneration was improved for the subsequent process of regeneration, the fiber organization was higher, and the extent of fibrosis was lower. The chronic phase experimental groups revealed that treatment with UCX(®) induced an increased number of regenerated fibers and thickening of the myelin sheet. Kinematics analysis showed that the ankle joint angle determined for untreated animals was significantly different from any of the treated groups at the instant of initial contact (IC). At opposite toe off (OT) and heel rise (HR), differences were found between untreated animals and the groups treated with either uCx(®) alone or UCX(®) administered with Floseal(®). Overall, the UCX(®) application presented

  12. Long-term effect of ropivacaine nanoparticles for sciatic nerve block on postoperative pain in rats

    PubMed Central

    Wang, Zi; Huang, Haizhen; Yang, Shaozhong; Huang, Shanshan; Guo, Jingxuan; Tang, Qi; Qi, Feng

    2016-01-01

    Purpose The analgesic effect of ropivacaine (Rop) for nerve block lasts only ~3–6 hours for single use. The aim of this study was to develop long-acting regional anesthetic Rop nanoparticles and investigate the effects of sciatic nerve block on postoperative pain in rats. Materials and methods Rop nanoparticles were developed using polyethylene glycol-co-polylactic acid (PELA). One hundred and twenty adult male Wistar rats were randomly divided into four groups (n=30, each): Con (control group; 0.9% saline, 200 µL), PELA (PELA group; 10 mg), Rop (Rop group; 0.5%, 200 µL), and Rop-PELA (Rop-PELA group; 10%, 10 mg). Another 12 rats were used for the detection of Rop concentration in plasma. The mechanical withdrawal threshold and thermal withdrawal latency were measured at 2 hours, 4 hours, 8 hours, 1 day, 2 days, 3 days, 5 days, and 7 days after incision. The expression of c-FOS was determined by immunohistochemistry at 2 hours, 8 hours, 48 hours, and 7 days. Nerve and organ toxicities were also evaluated at 7 days. Results The duration of Rop absorption in the plasma of the Rop-PELA group was longer (>8 hours) than that of the Rop group (4 hours). Mechanical withdrawal threshold and thermal withdrawal latency in the Rop-PELA group were higher than that in other groups (4 hours–3 days). c-FOS expression in the Rop-PELA group was lower than that in the control group at 2 hours, 8 hours, and 48 hours and lower than that in the Rop group at 8 hours and 48 hours after paw incision. Slight foreign body reactions were observed surrounding the sciatic nerve at 7 days. No obvious pathophysiological change was found in the major organs after Rop-PELA administration at 7 days. Conclusion Rop-PELA provides an effective analgesia for nerve block over 3 days after single administration, and the analgesic mechanism might be mediated by the regulation of spinal c-FOS expression. However, its potential long-term tissue toxicity needs to be further investigated. PMID:27274236

  13. Thermal hyperalgesia after sciatic nerve block in rat is transient and clinically insignificant.

    PubMed

    Janda, Allison; Lydic, Ralph; Welch, Kathleen B; Brummett, Chad M

    2013-01-01

    Ropivacaine has been associated with transient heat hyperalgesia in sciatic nerve blocks in rat. The goal of the present study was to evaluate the hypothesized presence of transient heat hyperalgesia after perineural injection of ropivacaine with a secondary subanalysis of 2 published studies. Paw withdrawal latency was used to assess the duration of sensory blockade and presence of heat hyperalgesia at 210, 240, 270, and 300 minutes and 24 hours after injection. The analysis revealed hyperalgesia at a single time point (240 minutes after injection; mean difference, -0.60 seconds; P = 0.012) that resolved within 30 minutes, and there was no other significant hyperalgesia at other time points. Although statistically significant, the single time point measurement represented only an 11% change from baseline and was no longer present 30 minutes later. These data support the need for a reevaluation of the interpretation that pain can be worsened by perineural ropivacaine injection.

  14. High-frequency stimulation selectively blocks different types of fibers in frog sciatic nerve.

    PubMed

    Joseph, Laveeta; Butera, Robert J

    2011-10-01

    Conduction block using high-frequency alternating current (HFAC) stimulation has been shown to reversibly block conduction through various nerves. However, unlike simulations and experiments on myelinated fibers, prior experimental work in our lab on the sea-slug, Aplysia, found a nonmonotonic relationship between frequency and blocking thresholds in the unmyelinated fibers. To resolve this discrepancy, we investigated the effect of HFAC waveforms on the compound action potential of the sciatic nerve of frogs. Maximal stimulation of the nerve produces a compound action potential consisting of the A-fiber and C-fiber components corresponding to the myelinated and unmyelinated fibers' response. In our study, HFAC waveforms were found to induce reversible block in the A-fibers and C-fibers for frequencies in the range of 5-50 kHz and for amplitudes from 0.1-1 mA. Although the A-fibers demonstrated the monotonically increasing threshold behavior observed in published literature, the C-fibers displayed a nonmonotonic relationship, analogous to that observed in the unmyelinated fibers of Aplysia. This differential blocking behavior observed in myelinated and unmyelinated fibers during application of HFAC waveforms has diverse implications for the fields of selective stimulation and pain management.

  15. Addition of Dexamethasone and Buprenorphine to Bupivacaine Sciatic Nerve Block: A Randomized, Controlled Trial

    PubMed Central

    YaDeau, Jacques T.; Paroli, Leonardo; Fields, Kara G.; Kahn, Richard L.; LaSala, Vincent R.; Jules-Elysee, Kethy M.; Kim, David H.; Haskins, Stephen C.; Hedden, Jacob; Goon, Amanda; Roberts, Matthew M.; Levine, David S.

    2015-01-01

    Background and Objectives Sciatic nerve block provides analgesia after foot and ankle surgery, but block duration may be insufficient. We hypothesized that perineural dexamethasone and buprenorphine would reduce pain scores at 24 hours. Methods Ninety patients received ultrasound-guided sciatic (25 mL 0.25% bupivacaine) and adductor canal (10 mL 0.25% bupivacaine) blockade, with random assignment into 3 groups (30 patients per group): control blocks + intravenous dexamethasone (4 mg) (control); control blocks + intravenous buprenorphine (150 mcg) + intravenous dexamethasone (intravenous buprenorphine); nerve blocks containing buprenorphine + dexamethasone (perineural). Patients received mepivacaine neuraxial anesthesia and postoperative oxycodone / acetaminophen, meloxicam, pregabalin, and ondansetron. Patients and assessors were blinded to group assignment. The primary outcome was pain with movement at 24 hours. Results There was no difference in pain with movement at 24 hours (median score 0). However, the perineural group had longer block duration vs control (45.6 vs 30.0 hr). Perineural patients had lower scores for “worst pain” vs control (median 0 vs 2). Both intravenous buprenorphine and perineural groups were less likely to use opioids on the day after surgery, vs control (28.6%, 28.6%, 60.7%, respectively). Nausea after intravenous buprenorphine (but not perineural buprenorphine) was severe, frequent, and bothersome. Conclusions Pain scores were very low at 24 hours after surgery in the context of multimodal analgesia and were not improved by additives. However, perineural buprenorphine and dexamethasone prolonged block duration, reduced the worst pain experienced, and reduced opioid use. Intravenous buprenorphine caused troubling nausea and vomiting. Future research is needed to confirm and extend these observations. PMID:25974277

  16. Naloxone reversible reduction in brain monoamine synthesis following sciatic nerve stimulation.

    PubMed

    Nissbrandt, H; Yao, T; Thorén, P; Svensson, T H

    1982-01-01

    Brain monoaminergic neurons seem to be influenced by endogenous opioid systems as judged from largely indirect evidence. In an attempt to more directly study this interaction, we have analyzed the effect of sciatic nerve stimulation (rectangular pulses, frequency 3 Hz, pulse duration 0.2 msec, current intensity 6-20 times muscle twitch threshold) on the in vivo rate of tyrosine-and tryptophanhydroxylation, respectively, in the rat brain. This stimulation procedure has previously been shown to evoke naloxone reversible pain threshold elevation and a longlasting blood pressure reduction rats, with maximum reached about 1.5 h after stimulation. The formation of DOPA and 5-HTP in various parts of the central nervous system during 30 min after inhibition of L-amino-acid-decarboxylase by NSD 1015 was measured. Two hours after the sciatic nerve stimulation procedure a significant decrease in DOPA formation was obtained in the cerebral cortex and in the spinal cord. This effect was reversed by pretreatment with a high dose of naloxone (15 mg/kg s.c., 10 min before stimulation). A reduction in 5-HTP formation was also obtained in the cerebral cortex, with a concomitant reduction in tryptophan concentration. These effects appeared to be antagonized by naloxone treatment. In the spinal cord there was no change in the 5-HTP accumulation after stimulation, but an increase after stimulation plus naloxone pretreatment was obtained. These data infer that the activity of some central monoamine systems, such as the NA pathways originating in locus coeruleus can be reduced by physiological activation of endogenous opioid systems. This effect of the acupuncture like stimulation procedure may be related to clinically reported actions of acupuncture stimulation, which apart from pain relief include, for example, antagonism of heroin abstinence symptoms.

  17. Dynamic Change and Target Prediction of Axon-Specific MicroRNAs in Regenerating Sciatic Nerve

    PubMed Central

    Phay, Monichan; Kim, Hak Hee; Yoo, Soonmoon

    2015-01-01

    Injury to axons in the peripheral nervous system induces rapid and local regenerative responses to form a new growth cone, and to generate a retrogradely transporting injury signal. The evidence for essential roles of intra-axonal protein synthesis during regeneration is now compelling. MicroRNA (miRNA) has recently been recognized as a prominent player in post-transcriptional regulation of axonal protein synthesis. Here, we directly contrast temporal changes of miRNA levels in the sciatic nerve following injury, as compared to those in an uninjured nerve using deep sequencing. Small RNAs (<200 nucleotides in length) were fractionated from the proximal nerve stumps to improve the representation of differential miRNA levels. Of 141 axoplasmic miRNAs annotated, 63 rat miRNAs showed significantly differential levels at five time points following injury, compared to an uninjured nerve. The differential changes in miRNA levels responding to injury were processed for hierarchical clustering analyses, and used to predict target mRNAs by Targetscan and miRanda. By overlapping these predicted targets with 2,924 axonally localizing transcripts previously reported, the overlapping set of 214 transcripts was further analyzed by the Gene Ontology enrichment and Ingenuity Pathway Analyses. These results suggest the possibility that the potential targets for these miRNAs play key roles in numerous neurological functions involved in ER stress response, cytoskeleton dynamics, vesicle formation, and neuro-degeneration and-regeneration. Finally, our results suggest that miRNAs could play a direct role in regenerative response and may be manipulated to promote regenerative ability of injured nerves. PMID:26331719

  18. Effect of adjuvants on the action of local anesthetics in isolated rat sciatic nerves

    PubMed Central

    Yilmaz, Eser; Gold, Michael S.; Hough, Karen A.; Gebhart, G.F.; Williams, Brian A.

    2013-01-01

    Background and Objectives There is increasing clinical use of adjuvant drugs to prolong the duration of local anesthetic-induced block of peripheral nerves. However, the mechanistic understanding regarding drug interactions between these compounds in the periphery is quite limited. Accordingly, we undertook this study to determine whether selected adjuvants are efficacious in blocking action potential propagation in peripheral nerves at concentrations used clinically, and whether these drugs influence peripheral nerve block produced by local anesthetics. Methods Isolated rat sciatic nerves were used to assess (1) the efficacy of buprenorphine, clonidine, dexamethasone, or midazolam, alone and in combination, on action potential propagation; and (2) their influence on the blocking actions of local anesthetics ropivacaine and lidocaine. Compound action potentials (CAPs) from A- and C-fibers were studied before and after drug application. Results At estimated clinical concentrations, neither buprenorphine nor dexamethasone affected either A- or C-waves of the CAP. Clonidine produced a small, but significant attenuation of the C-wave amplitude. Midazolam attenuated both A- and C-wave amplitudes, but with greater potency on the C-wave. The combination of clonidine, buprenorphine, and dexamethasone had no influence on the potency or duration of local anesthetic- or midazolam-induced block of A-and C-waves of the CAP. Conclusions These results suggest that the reported clinical efficacy of clonidine, buprenorphine, and dexamethasone influence the actions of local anesthetics via indirect mechanisms. Further identification of these indirect mechanisms may enable the development of novel approaches to achieve longer duration, modality-specific peripheral nerve block. PMID:22430023

  19. Nerve Wrapping of the Sciatic Nerve With Acellular Dermal Matrix in Chronic Complete Proximal Hamstring Ruptures and Ischial Apophyseal Avulsion Fractures

    PubMed Central

    Haus, Brian M.; Arora, Danny; Upton, Joseph; Micheli, Lyle J.

    2016-01-01

    Background: Patients with chronic injuries of the proximal hamstring can develop significant impairment because of weakness of the hamstring muscles, sciatic nerve compression from scar formation, or myositis ossificans. Purpose: To describe the surgical outcomes of patients with chronic injury of the proximal hamstrings who were treated with hamstring repair and sciatic neurolysis supplemented with nerve wrapping with acellular dermal matrix. Study Design: Retrospective case series; Level of evidence, 4. Methods: Fifteen consecutive patients with a diagnosis of chronic complete proximal hamstring rupture or chronic ischial tuberosity apophyseal avulsion fracture (mean age, 39.67 years; range, 14-69 years) were treated with proximal hamstring repair and sciatic neurolysis supplemented with nerve wrapping with acellular dermal matrix. Nine patients had preoperative sciatica, and 6 did not. Retrospective chart review recorded clinical outcomes measured by the degree of pain relief, the rate of return to activities, and associated postoperative complications. Results: All 15 patients were followed in the postoperative period for an average of 16.6 months. Postoperatively, there were 4 cases of transient sciatic nerve neurapraxia. Four patients (26%) required postoperative betamethasone sodium phosphate (Celestone Soluspan) injectable suspension USP 6 mg/mL. Among the 9 patients with preoperative sciatica, 6 (66%) had a good or excellent outcome and were able to return to their respective activities/sports; 3 (33%) had persistent chronic pain. One of these had persistent sciatic neuropathy that required 2 surgical reexplorations and scar excision after development of recurrent extraneural scar formation. Among the 6 without preoperative sciatica, 100% had a good or excellent outcomes and 83% returned to their respective activities/sports. Better outcomes were observed in younger patients, as the 3 cases of persistent chronic sciatic pain were in patients older than 45

  20. Respective pharmacological features of neuropathic-like pain evoked by intrathecal BDNF versus sciatic nerve ligation in rats.

    PubMed

    M'Dahoma, Saïd; Barthélemy, Sandrine; Tromilin, Claire; Jeanson, Tiffany; Viguier, Florent; Michot, Benoit; Pezet, Sophie; Hamon, Michel; Bourgoin, Sylvie

    2015-11-01

    Numerous reported data support the idea that Brain Derived Neurotrophic Factor (BDNF) is critically involved in both depression and comorbid pain. The possible direct effect of BDNF on pain mechanisms was assessed here and compared with behavioral/neurobiological features of neuropathic pain caused by chronic constriction injury to the sciatic nerve (CCI-SN). Sprague-Dawley male rats were either injected intrathecally with BDNF (3.0 ng i.t.) or subjected to unilateral CCI-SN. Their respective responses to anti-hyperalgesic drugs were assessed using the Randall-Selitto test and both immunohistochemical and RT-qPCR approaches were used to investigate molecular/cellular mechanisms underlying hyperalgesia in both models. Long lasting hyperalgesia and allodynia were induced by i.t. BDNF in intact healthy rats like those found after CCI-SN. Acute treatment with the BDNF-TrkB receptor antagonist cyclotraxin B completely prevented i.t. BDNF-induced hyperalgesia and partially reversed this symptom in both BDNF-pretreated and CCI-SN lesioned rats. Acute administration of the anticonvulsant pregabalin, the NMDA receptor antagonist ketamine, the opioid analgesics morphine and tapentadol or the antidepressant agomelatine also transiently reversed hyperalgesia in both i.t. BDNF injected- and CCI-SN lesioned-rats. Marked induction of microglia activation markers (OX42, Iba1, P-p38), proinflammatory cytokine IL-6, NMDA receptor subunit NR2B and BDNF was found in spinal cord and/or dorsal root ganglia of CCI-SN rats. A long lasting spinal BDNF overexpression was also observed in BDNF i.t. rats, indicating an autocrine self-induction, with downstream long lasting TrkB-mediated neuropathic-like pain. Accordingly, TrkB blockade appeared as a relevant approach to alleviate not only i.t. BDNF- but also nerve lesion-evoked neuropathic pain. PMID:26343858

  1. F-actin distribution at nodes of Ranvier and Schmidt-Lanterman incisures in mammalian sciatic nerves.

    PubMed

    Kun, Alejandra; Canclini, Lucía; Rosso, Gonzalo; Bresque, Mariana; Romeo, Carlos; Hanusz, Alicia; Cal, Karina; Calliari, Aldo; Sotelo Silveira, José; Sotelo, José R

    2012-07-01

    Very little is known about the function of the F-actin cytoskeleton in the regeneration and pathology of peripheral nerve fibers. The actin cytoskeleton has been associated with maintenance of tissue structure, transmission of traction and contraction forces, and an involvement in cell motility. Therefore, the state of the actin cytoskeleton strongly influences the mechanical properties of cells and intracellular transport therein. In this work, we analyze the distribution of F-actin at Schmidt-Lanterman Incisures (SLI) and nodes of Ranvier (NR) domains in normal, regenerating and pathologic Trembler J (TrJ/+) sciatic nerve fibers, of rats and mice. F-actin was quantified and it was found increased in TrJ/+, both in SLI and NR. However, SLI and NR of regenerating rat sciatic nerve did not show significant differences in F-actin, as compared with normal nerves. Cytochalasin-D and Latrunculin-A were used to disrupt the F-actin network in normal and regenerating rat sciatic nerve fibers. Both drugs disrupt F-actin, but in different ways. Cytochalasin-D did not disrupt Schwann cell (SC) F-actin at the NR. Latrunculin-A did not disrupt F-actin at the boundary region between SC and axon at the NR domain. We surmise that the rearrangement of F-actin in neurological disorders, as presented here, is an important feature of TrJ/+ pathology as a Charcot-Marie-Tooth (CMT) model.

  2. Post-evaluation of the neurophaties treatment post-trauma with therapeutic laser. Model in sciatic nerve of frog

    SciTech Connect

    Escobar, Antonio S.; Ocampo, Arcelia F. M.; Hernandez, Maria G. H.; Jasso, Jose L. C.

    2010-05-31

    The purpose of this study was to evaluate the compound nerve action potential amplitude and latency measured to determine the degree of myelination and the number of fibers stimulated in a model of stimulated frog sciatic nerve laser at 810 nm as perioperative treatment after injury. It used 30 bullfrogs (Rana catesbeiana) to obtain 60 sciatic nerves forming four groups, groups 1 and 2 worked with nerves in vitro, were dissected in humid chambers for placing isolated organ, was recorded on compound nerve action potential, the second group laser was applied at 24, 48, 72, 96 and 120 hours and at the same time were placed in 10% formalin. Groups 3 and 4 are worked in vivo localizing the nerve and causing damage through compression, occurred over the compound nerve action potential to assess the degree of myelination and the number of fibers stimulated, the group 4 was applied to 810 nm laser (500 Hz, 10 J, 200 mW) after injury, after 48 hours, three frogs were sacrificed by introducing the nerves in 10% formalin. The latency recorded by stimulating the sciatic nerve of frog to 0.5 mA and 100 ms in groups 1 and 2 show significant differences (p<0.001 and p<000) as in the amplitude (p<000 and p<000). Groups 3 and 4, which was stimulated at 100 mA and 100 ms latency showed no statistically significant difference (p>000), as to the extent, if any statistically significant difference. (p<0.001 and p<0.000). The laser produces a favorable response in the treatment of paresthesia (post-traumatic neuropathy).

  3. Post-evaluation of the neurophaties treatment post-trauma with therapeutic laser. Model in sciatic nerve of frog

    NASA Astrophysics Data System (ADS)

    Escobar, Antonio S.; Ocampo, Arcelia F. M.; Hernández, María G. H.; Jasso, José L. C.; Lira, Maricela O. F.; Flores, Mariana A.; Balderrama, Vicente L.

    2010-05-01

    The purpose of this study was to evaluate the compound nerve action potential amplitude and latency measured to determine the degree of myelination and the number of fibers stimulated in a model of stimulated frog sciatic nerve laser at 810 nm as perioperative treatment after injury. It used 30 bullfrogs (Rana catesbeiana) to obtain 60 sciatic nerves forming four groups, groups 1 and 2 worked with nerves in vitro, were dissected in humid chambers for placing isolated organ, was recorded on compound nerve action potential, the second group laser was applied at 24, 48, 72, 96 and 120 hours and at the same time were placed in 10% formalin. Groups 3 and 4 are worked in vivo localizing the nerve and causing damage through compression, occurred over the compound nerve action potential to assess the degree of myelination and the number of fibers stimulated, the group 4 was applied to 810 nm laser (500 Hz, 10 J, 200 mW) after injury, after 48 hours, three frogs were sacrificed by introducing the nerves in 10% formalin. The latency recorded by stimulating the sciatic nerve of frog to 0.5 mA and 100 ms in groups 1 and 2 show significant differences (p<0.001 and p<000) as in the amplitude (p<000 and p<000). Groups 3 and 4, which was stimulated at 100 mA and 100 ms latency showed no statistically significant difference (p>000), as to the extent, if any statistically significant difference. (p<0.001 and p<0.000). The laser produces a favorable response in the treatment of paresthesia (post-traumatic neuropathy).

  4. Allotransplanted DRG neurons or Schwann cells affect functional recovery in a rodent model of sciatic nerve injury

    PubMed Central

    Liu, Weimin; Markman, John D.; Gelbard, Harris A.; Huang, Jason H.

    2015-01-01

    Objective In this study, the functional recoveries of Sprague-Dawley rats following repair of a complete sciatic nerve transection using allotransplanted dorsal root ganglion (DRG) neurons or Schwann cells were examined using a number of outcome measures. Methods Four groups were compared: (1) repair with a nerve guide conduit seeded with allotransplanted Schwann cells harvested from Wistar rats, (2) repair with a nerve guide conduit seeded with DRG neurons, (3) repair with solely a nerve guide conduit, and (4) sham-surgery animals where the sciatic nerve was left intact. The results corroborated our previous reported histology findings and measures of immunogenicity. Results The Wistar-DRG-treated group achieved the best recovery, significantly outperforming both the Wistar-Schwann group and the nerve guide conduit group in the Von Frey assay of touch response (P < 0.05). Additionally, Wistar-DRG and Wistar-Schwann seeded repairs showed lower frequency and severity in an autotomy measure of the self-mutilation of the injured leg because of neuralgia. Conclusion These results suggest that in complete peripheral nerve transections, surgical repair using nerve guide conduits with allotransplanted DRG and Schwann cells may improve recovery, especially DRG neurons, which elicit less of an immune response. PMID:24836462

  5. Mice Lacking GD3 Synthase Display Morphological Abnormalities in the Sciatic Nerve and Neuronal Disturbances during Peripheral Nerve Regeneration

    PubMed Central

    Ribeiro-Resende, Victor Túlio; Gomes, Tiago Araújo; de Lima, Silmara; Nascimento-Lima, Maiara; Bargas-Rega, Michele; Santiago, Marcelo Felipe; Reis, Ricardo Augusto de Melo; de Mello, Fernando Garcia

    2014-01-01

    The ganglioside 9-O-acetyl GD3 is overexpressed in peripheral nerves after lesioning, and its expression is correlated with axonal degeneration and regeneration in adult rodents. However, the biological roles of this ganglioside during the regenerative process are unclear. We used mice lacking GD3 synthase (Siat3a KO), an enzyme that converts GM3 to GD3, which can be further converted to 9-O-acetyl GD3. Morphological analyses of longitudinal and transverse sections of the sciatic nerve revealed significant differences in the transverse area and nerve thickness. The number of axons and the levels of myelin basic protein were significantly reduced in adult KO mice compared to wild-type (WT) mice. The G-ratio was increased in KO mice compared to WT mice based on quantification of thin transverse sections stained with toluidine blue. We found that neurite outgrowth was significantly reduced in the absence of GD3. However, addition of exogenous GD3 led to neurite growth after 3 days, similar to that in WT mice. To evaluate fiber regeneration after nerve lesioning, we compared the regenerated distance from the lesion site and found that this distance was one-fourth the length in KO mice compared to WT mice. KO mice in which GD3 was administered showed markedly improved regeneration compared to the control KO mice. In summary, we suggest that 9-O-acetyl GD3 plays biological roles in neuron-glia interactions, facilitating axonal growth and myelination induced by Schwann cells. Moreover, exogenous GD3 can be converted to 9-O-acetyl GD3 in mice lacking GD3 synthase, improving regeneration. PMID:25330147

  6. Gallic acid and exercise training improve motor function, nerve conduction velocity but not pain sense reflex after experimental sciatic nerve crush in male rats

    PubMed Central

    Hajimoradi, Maryam; Fazilati, Mohammad; Gharib-Naseri, Mohammad Kazem; Sarkaki, Alireza

    2015-01-01

    Objective: The aim of present study was to evaluate the effects of oral administration of gallic acid (GA) for 21 days alone and in combination with exercise on nerve conduction velocity and sensory and motor functions in rats with sciatic nerve crush. Materials and Methods: Seventy adult male Wistar rats (250-300 g) were divided randomly into 7 groups with 10 in each: 1) Control (Cont), 2) Crushed + Vehicle (Cr +Veh), 3-5) Crushed + gallic acid (Cr+GA) (50, 100, and 200 mg/kg/2 mL, orally), 6) Crushed + exercise (Cr+Exe), and 7) Crushed + exercise + effective dose of gallic acid (Cr+Exe +GA200) for 21 days. In order to establish an animal model of sciatic nerve crush, equivalent to 7 kg of force pressed on 2-3 mm of sciatic nerve for 30 s, three times with 30 s intervals. Pain sense reflex in hot plate, motor coordination in rotarod, and sciatic nerve conduction velocity (SNCV) in all groups were tested. Data were analyzed using one-way ANOVA followed by Tukey’s post hoc test and p<0.05 has assigned as the significant difference. Results: Pain threshold was increased significantly in untreated crushed rats while motor function and SNCV were decreased in all groups with nerve crush (p<0.05, p<0.01, p<0.001 vs. control). Pain reflex latency was not changed in treated groups. Motor coordination and SNCV were improved in groups Cr+GA200 and Cr+Exe + GA200 (p<0.05, p<0.01 vs. Cr+Veh). Conclusion: GA, dose-dependently, may have therapeutic potential to improve the peripheral nerve degeneration, which is most likely related, at least in part, to its antioxidant and therapeutic properties. PMID:26445710

  7. Cytidine 5′-diphosphocholine administration prevents peripheral neuropathic pain after sciatic nerve crush injury in rats

    PubMed Central

    Emril, Dessy R; Wibowo, Samekto; Meliala, Lucas; Susilowati, Rina

    2016-01-01

    Background Cytidine 5′-diphosphocholine (citicoline) has been shown to have beneficial effects in central nervous system injury as well as in motoric functional recovery after peripheral nerve injury. This study aimed to examine the effect of citicoline on prevention of neuropathic pain in a rat model of sciatic nerve crush injury. Methods Forty experimental rats were divided into four groups. In three groups, the right sciatic nerves were crushed in the mid-thigh region, and a gelatin sponge moistened with 0.4 or 0.8 mL of 100 µmol/L citicoline, or saline 0.4 mL in the control group, was applied. The fourth group of rats was sham-operated, ie the sciatic nerve was exposed with no crush. Functional assessments were performed 4 weeks after crush injury. von Frey filaments (100 g threshold) were used to assess neuropathic pain. In addition, the sciatic functional index and extensor postural thrust (EPT) tests were used to assess motoric function. Results The crush/citicoline 0.4 mL group had a lower percentage of pain (23.53%, n=17) compared with the crush/saline group (53.33%, n=15, P<0.005). The crush/citicoline 0.4 mL group also showed better motoric recovery, as seen in stronger EPT results (P<0.001). However, the sciatic functional index analysis did not show significant differences between groups (P=0.35). The crush/citicoline 0.8 mL group showed a higher percentage of pain (66.67%, n=18) and less EPT recovery. These results may be explained by more severe nerve injury due to compression with a larger administered volume. Conclusion In situ administration of 0.4 mL of 100 µmol/L citicoline prevents the occurrence of neuropathic pain and induces motoric recovery, evaluated by EPT test, 4 weeks after sciatic nerve injury. PMID:27284264

  8. Stress and strain analysis on the anastomosis site sutured with either epineurial or perineurial sutures after simulation of sciatic nerve injury☆

    PubMed Central

    Liu, Guangyao; Zhang, Qiao; Jin, Yan; Gao, Zhongli

    2012-01-01

    The magnitude of tensile stress and tensile strain at an anastomosis site under physiological stress is an important factor for the success of anastomosis following suturing in peripheral nerve injury treatment. Sciatic nerves from fresh adult cadavers were used to create models of sciatic nerve injury. The denervated specimens underwent epineurial and perineurial suturing. The elastic modulus (40.96 ± 2.59 MPa) and Poisson ratio (0.37 ± 0.02) of the normal sciatic nerve were measured by strain electrical measurement. A resistance strain gauge was pasted on the front, back, left, and right of the edge of the anastomosis site after suturing. Strain electrical measurement results showed that the stress and strain values of the sciatic nerve following perineurial suturing were lower than those following epineurial suturing. Scanning electron microscopy revealed that the sciatic nerve fibers were disordered following epineurial compared with perineurial suturing. These results indicate that the effect of perineurial suturing in sciatic nerve injury repair is better than that of epineurial suturing. PMID:25538753

  9. A Silk Fibroin/Collagen Nerve Scaffold Seeded with a Co-Culture of Schwann Cells and Adipose-Derived Stem Cells for Sciatic Nerve Regeneration.

    PubMed

    Xu, Yunqiang; Zhang, Zhenhui; Chen, Xuyi; Li, Ruixin; Li, Dong; Feng, Shiqing

    2016-01-01

    As a promising alternative to autologous nerve grafts, tissue-engineered nerve grafts have been extensively studied as a way to bridge peripheral nerve defects and guide nerve regeneration. The main difference between autogenous nerve grafts and tissue-engineered nerve grafts is the regenerative microenvironment formed by the grafts. If an appropriate regenerative microenvironment is provided, the repair of a peripheral nerve is feasible. In this study, to mimic the body's natural regenerative microenvironment closely, we co-cultured Schwann cells (SCs) and adipose-derived stem cells (ADSCs) as seed cells and introduced them into a silk fibroin (SF)/collagen scaffold to construct a tissue-engineered nerve conduit (TENC). Twelve weeks after the three different grafts (plain SF/collagen scaffold, TENC, and autograft) were transplanted to bridge 1-cm long sciatic nerve defects in rats, a series of electrophysiological examinations and morphological analyses were performed to evaluate the effect of the tissue-engineered nerve grafts on peripheral nerve regeneration. The regenerative outcomes showed that the effect of treatment with TENCs was similar to that with autologous nerve grafts but superior to that with plain SF/collagen scaffolds. Meanwhile, no experimental animals had inflammation around the grafts. Based on this evidence, our findings suggest that the TENC we developed could improve the regenerative microenvironment and accelerate nerve regeneration compared to plain SF/collagen and may serve as a promising strategy for peripheral nerve repair. PMID:26799619

  10. Goji fruit (Lycium barbarum) protects sciatic nerve function against crush injury in a model of diabetic stress.

    PubMed

    Simonyan, K V; Avetisyan, L G; Chavushyan, V A

    2016-09-01

    Excess fructose consumption causes changes in functioning of the central and peripheral nervous systems, which increase the vulnerability of peripheral nerves to traumatic injury. The aim of this study was to evaluate the electrophysiological parameters of responses of motoneurons of the spinal cord at high-frequency stimulation of the distal part of the injured sciatic nerve in a model of diabetic stress under action of Lycium barbarum (LB). Male albino rats were given with drinking water with 50% concentration of dietary fructose for 6 weeks. Starting on the 7th week a crush injury of the left sciatic nerve was carried out. Some of the animals received fructose post-injury for 3 weeks and some of the animals received fructose+dry LB fruits for 3 weeks. In the fructose+crush+LВ group a relatively proportional division of tetanic and posttetanic potentiation and depression in responses of ipsilateral and contralateral motoneurons was observed, which would suggest the modulatory role of LB in short-term synaptic plasticity formation. Generally, LB fruit is able to modulate central nervous system reorganization, amplifying positive adaptive changes that improve functional recovery and promote selective target reinnervation in high fructose-diet rats with sciatic nerve crush-injury. PMID:27424529

  11. Intraneural dexamethasone applied simultaneously to rat sciatic nerve constriction delays the development of hyperalgesia and allodynia.

    PubMed

    Bastos, Leandro F S; Medeiros, Daniel C; Vieira, Rafael P; Watkins, Linda R; Coelho, Márcio M; Moraes, Márcio F D

    2012-02-21

    Although neuroimmune interactions associated with the development of pain sensitization in models of neuropathic pain have been widely studied, there are some aspects that require further investigation. Thus, we aimed to evaluate whether the local intraneural or perineural injections of dexamethasone, an efficacious anti-inflammatory and immunosuppressant drug, delays the development of both thermal hyperalgesia and mechanical allodynia in an experimental model of neuropathic pain in rats. Hargreaves and electronic von Frey tests were applied. The chronic constriction injury (CCI) of right sciatic nerve was performed. Single intraneural dexamethasone administration at the moment of constriction delayed the development of sensitization for thermal hyperalgesia and mechanical allodynia. However, perineural administration of dexamethasone, at the highest dose, did not delay experimental pain development. These results show that inflammation/immune response at the site of nerve lesion is an essential trigger for the pathological changes that lead to both hyperalgesia and allodynia. In conclusion, this approach opens new opportunities to study cellular and molecular neuroimmune interactions associated with the development of pain derived from peripheral neuropathies. PMID:22240103

  12. Affinity-based release of glial-derived neurotrophic factor from fibrin matrices enhances sciatic nerve regeneration†

    PubMed Central

    Wood, Matthew D.; Moore, Amy M.; Hunter, Daniel A.; Tuffaha, Sami; Borschel, Gregory H.; Mackinnon, Susan E.; Sakiyama-Elbert, Shelly E.

    2008-01-01

    Glial-derived neurotrophic factor (GDNF) promotes both sensory and motor neuron survival. The delivery of GDNF to the peripheral nervous system has been shown to enhance regeneration following injury. In this study we evaluated the effect of affinity-based delivery of GDNF from a fibrin matrix in a nerve guidance conduit on nerve regeneration in a 13 mm rat sciatic nerve defect. Seven experimental groups were evaluated which received GDNF or nerve growth factor (NGF) with the delivery system within the conduit, control groups excluding one or more components of the delivery system, and nerve isografts. Nerves were harvested 6 weeks after treatment for analysis by histomorphometry and electron microscopy. The use of the delivery system (DS) with either GDNF or NGF resulted in a higher frequency of nerve regeneration vs. control groups, as evidenced by a neural structure spanning the 13 mm gap. The GDNF DS and NGF DS groups were also similar to the nerve isograft group in measures of nerve fiber density, percent neural tissue and myelinated area measurements, but not in terms of total fiber counts. In addition, both groups contained a significantly greater percentage of larger diameter fibers, with GDNF DS having the largest in comparison to all groups, suggesting more mature neural content. The delivery of GDNF via the affinity-based delivery system can enhance peripheral nerve regeneration through a silicone conduit across a critical nerve gap and offers insight into potential future alternatives to the treatment of peripheral nerve injuries. PMID:19103514

  13. Sciatic nerve repair with tissue engineered nerve: Olfactory ensheathing cells seeded poly(lactic-co-glygolic acid) conduit in an animal model

    PubMed Central

    Tan, C W; Ng, M H; Ohnmar, H; Lokanathan, Y; Nur-Hidayah, H; Roohi, S A; Ruszymah, BHI; Nor-Hazla, M H; Shalimar, A; Naicker, A S

    2013-01-01

    Background and Aim: Synthetic nerve conduits have been sought for repair of nerve defects as the autologous nerve grafts causes donor site morbidity and possess other drawbacks. Many strategies have been investigated to improve nerve regeneration through synthetic nerve guided conduits. Olfactory ensheathing cells (OECs) that share both Schwann cell and astrocytic characteristics have been shown to promote axonal regeneration after transplantation. The present study was driven by the hypothesis that tissue-engineered poly(lactic-co-glycolic acid) (PLGA) seeded with OECs would improve peripheral nerve regeneration in a long sciatic nerve defect. Materials and Methods: Sciatic nerve gap of 15 mm was created in six adult female Sprague-Dawley rats and implanted with PLGA seeded with OECs. The nerve regeneration was assessed electrophysiologically at 2, 4 and 6 weeks following implantation. Histopathological examination, scanning electron microscopic (SEM) examination and immunohistochemical analysis were performed at the end of the study. Results: Nerve conduction studies revealed a significant improvement of nerve conduction velocities whereby the mean nerve conduction velocity increases from 4.2 ΁ 0.4 m/s at week 2 to 27.3 ΁ 5.7 m/s at week 6 post-implantation (P < 0.0001). Histological analysis revealed presence of spindle-shaped cells. Immunohistochemical analysis further demonstrated the expression of S100 protein in both cell nucleus and the cytoplasm in these cells, hence confirming their Schwann-cell-like property. Under SEM, these cells were found to be actively secreting extracellular matrix. Conclusion: Tissue-engineered PLGA conduit seeded with OECs provided a permissive environment to facilitate nerve regeneration in a small animal model. PMID:24379458

  14. Calpain 3 Expression Pattern during Gastrocnemius Muscle Atrophy and Regeneration Following Sciatic Nerve Injury in Rats

    PubMed Central

    Wu, Ronghua; Yan, Yingying; Yao, Jian; Liu, Yan; Zhao, Jianmei; Liu, Mei

    2015-01-01

    Calpain 3 (CAPN3), also known as p94, is a skeletal muscle-specific member of the calpain family that is involved in muscular dystrophy; however, the roles of CAPN3 in muscular atrophy and regeneration are yet to be understood. In the present study, we attempted to explain the effect of CAPN3 in muscle atrophy by evaluating CAPN3 expression in rat gastrocnemius muscle following reversible sciatic nerve injury. After nerve injury, the wet weight ratio and cross sectional area (CSA) of gastrocnemius muscle were decreased gradually from 1–14 days and then recovery from 14–28 days. The active form of CAPN3 (~62 kDa) protein decreased slightly on day 3 and then increased from day 7 to 14 before a decrease from day 14 to 28. The result of linear correlation analysis showed that expression of the active CAPN3 protein level was negatively correlated with muscle wet weight ratio. CAPN3 knockdown by short interfering RNA (siRNA) injection improved muscle recovery on days 7 and 14 after injury as compared to that observed with control siRNA treatment. Depletion of CAPN3 gene expression could promote myoblast differentiation in L6 cells. Based on these findings, we conclude that the expression pattern of the active CAPN3 protein is linked to muscle atrophy and regeneration following denervation: its upregulation during early stages may promote satellite cell renewal by inhibiting differentiation, whereas in later stages, CAPN3 expression may be downregulated to stimulate myogenic differentiation and enhance recovery. These results provide a novel mechanistic insight into the role of CAPN3 protein in muscle regeneration after peripheral nerve injury. PMID:26569227

  15. Effect of Pulsed Radiofrequency on Rat Sciatic Nerve Chronic Constriction Injury: A Preliminary Study

    PubMed Central

    Li, Duo-Yi; Meng, Lan; Ji, Nan; Luo, Fang

    2015-01-01

    Background: Pulsed radiofrequency (PRF) application to the dorsal root ganglia can reduce neuropathic pain (NP) in animal models, but the effect of PRF on damaged peripheral nerves has not been examined. We investigated the effect of PRF to the rat sciatic nerve (SN) on pain-related behavior and SN ultrastructure following chronic constriction injury (CCI). Methods: The analgesic effect was measured by hindpaw mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL). Twenty rats with NP induced by ligating the common SN were then randomly divided into a PRF treatment group and a sham group. The contralateral SN served as a control. The MWT and TWL were determined again 2, 4, 6, 8, 10, 12, and 14 days after the PRF or sham treatment. On day 14, ipsilateral and contralateral common SNs were excised and examined by electron microscopy. Results: Ipsilateral MWT was significantly reduced and TWL significantly shorter compared to the contralateral side 14 days after CCI (both P = 0.000). In the PRF group, MWT was significantly higher and TWL significantly longer 14 days after the PRF treatment compared to before PRF treatment (both P = 0.000), while no such difference was observed in the sham group (P > 0.05). Electron microscopy revealed extensive demyelination and collagen fiber formation in the ipsilateral SN of sham-treated rats but sparse demyelination and some nerve fiber regrowth in the PRF treatment group. Conclusions: Hyperalgesia is relieved, and ultrastructural damage ameliorated after direct PRF treatment to the SN in the CCI rat model of NP. PMID:25673460

  16. Three-dimensional conformal intensity-modulated radiation therapy of left femur foci does not damage the sciatic nerve

    PubMed Central

    Xu, Wanlong; Zhao, Xibin; Wang, Qing; Sun, Jungang; Xu, Jiangbo; Zhou, Wenzheng; Wang, Hao; Yan, Shigui; Yuan, Hong

    2014-01-01

    During radiotherapy to kill femoral hydatid tapeworms, the sciatic nerve surrounding the focus can be easily damaged by the treatment. Thus, it is very important to evaluate the effects of radiotherapy on the surrounding nervous tissue. In the present study, we used three-dimensional, conformal, intensity-modulated radiation therapy to treat bilateral femoral hydatid disease in Meriones meridiani. The focus of the hydatid disease on the left femur was subjected to radiotherapy (40 Gy) for 14 days, and the right femur received sham irradiation. Hematoxylin-eosin staining, electron microscopy, and terminal deoxynucleotidyl transferase-dUTP nick end labeling assays on the left femurs showed that the left sciatic nerve cell structure was normal, with no obvious apoptosis after radiation. Trypan blue staining demonstrated that the overall protoscolex structure in bone parasitized with Echinococcus granulosus disappeared in the left femur of the animals after treatment. The mortality of the protoscolex was higher in the left side than in the right side. The succinate dehydrogenase activity in the protoscolex in bone parasitized with Echinococcus granulosus was lower in the left femur than in the right femur. These results suggest that three-dimensional conformal intensity-modulated radiation therapy achieves good therapeutic effects on the secondary bone in hydatid disease in Meriones meridiani without damaging the morphology or function of the sciatic nerve. PMID:25422645

  17. Combined continuous "3-in-1" and sciatic nerve blocks provide improved postoperative analgesia with no correlation to catheter tip location after unilateral total knee arthroplasty.

    PubMed

    Rajeev, Subramanyam; Batra, Yatindra Kumar; Panda, Nidhi Bidyut; Kumar, Mukesh; Nagi, Onkar Nath

    2007-12-01

    This study assessed the efficacy and duration of postoperative analgesia after continuous sciatic nerve block with and without continuous "3-in-1" block with bupivacaine after unilateral total knee arthroplasty and determined catheter tip correlation with analgesia. Thirty patients were randomized into 2 groups. Results suggested significantly reduced pain and rescue analgesic requirement in combined sciatic and 3-in-1 (group TS) compared to 3-in-1 group alone (group T). The postoperative pain-free interval and satisfaction score was significantly higher in the combined group (P < .05). The percentage of catheters in the ideal position was 53.3% for 3-in-1 and 93.3% for sciatic nerve. In conclusion, continuous sciatic nerve block when added to continuous 3-in-1 block provides a better quality of analgesia with lesser requirements of rescue analgesics without the need for routine radiographic conformation.

  18. Thermographic evaluation of hind paw skin temperature and functional recovery of locomotion after sciatic nerve crush in rats

    PubMed Central

    Z. Sacharuk, Viviane; A. Lovatel, Gisele; Ilha, Jocemar; Marcuzzo, Simone; Severo do Pinho, Alexandre; L. Xavier, Léder; A. Zaro, Milton; Achaval, Matilde

    2011-01-01

    INTRODUCTION: Peripheral nerves are often damaged by direct mechanical injury, diseases, and tumors. The peripheral nerve injuries that result from these conditions can lead to a partial or complete loss of motor, sensory, and autonomic functions, which in turn are related to changes in skin temperature, in the involved segments of the body. The aim of this study was to evaluate the changes in hind paw skin temperature after sciatic nerve crush in rats in an attempt to determine whether changes in skin temperature correlate with the functional recovery of locomotion. METHODS: Wistar rats were divided into three groups: control (n = 7), sham (n = 25), and crush (n = 25). All groups were subjected to thermographic, functional, and histological assessments. RESULTS: ΔT in the crush group was different from the control and sham groups at the 1st, 3rd and 7rd postoperative days (p<0.05). The functional recovery from the crush group returned to normal values between the 3rd and 4th week post-injury, and morphological analysis of the nerve revealed incomplete regeneration at the 4th week after injury. DISCUSSION: This study is the first demonstration that sciatic nerve crush in rats induces an increase in hind paw skin temperature and that skin temperature changes do not correlate closely with functional recovery PMID:21876984

  19. Nociceptive and Neuronal Evaluation of the Sciatic Nerve of Wistar Rats Subjected to Compression Injury and Treated with Resistive Exercise

    PubMed Central

    Antunes, Juliana Sobral; Lovison, Keli; Karvat, Jhenifer; Peretti, Ana Luiza; Vieira, Lizyana; Higuchi, Guilherme Hideaki; Ribeiro, Lucinéia de Fátima Chasko

    2016-01-01

    Background. To investigate the climb stairs resistance exercise on nociception and axonal regeneration in the sciatic nerve of rats. Methods. 24 Wistar rats were divided: control group (CG—no injury), exercise group (EG—no injury with physical exercise), lesion group (LG—injury, but without exercise), and treated group (LEG—injury and physical exercise). LG and LEG were subjected to sciatic nerve compression with hemostat. From the 3rd day after injury began treatment with exercise, and after 22 days occurs the removal of a nerve fragment for morphological analysis. Results. Regarding allodynia, CG obtained values less than EG (p = 0.012) and larger than LG and LEG (p < 0.001). Histological results showed that CG and EG had normal appearance, as LG and LEG showed up with large amounts of inflammatory infiltration, degeneration and disruption of nerve fibers, and reduction of the myelin sheath; however LEG presented some regenerated fibers. From the morphometric data there were significant differences, for nerve fiber diameter, comparing CG with LG and LEG and comparing axon diameter and the thickness of the myelin of the CG to others. Conclusion. Climb stairs resistance exercise was not effective to speed up the regenerative process of axons.

  20. Nociceptive and Neuronal Evaluation of the Sciatic Nerve of Wistar Rats Subjected to Compression Injury and Treated with Resistive Exercise.

    PubMed

    Antunes, Juliana Sobral; Lovison, Keli; Karvat, Jhenifer; Peretti, Ana Luiza; Vieira, Lizyana; Higuchi, Guilherme Hideaki; Brancalhão, Rose Meire Costa; Ribeiro, Lucinéia de Fátima Chasko; Bertolini, Gladson Ricardo Flor

    2016-01-01

    Background. To investigate the climb stairs resistance exercise on nociception and axonal regeneration in the sciatic nerve of rats. Methods. 24 Wistar rats were divided: control group (CG-no injury), exercise group (EG-no injury with physical exercise), lesion group (LG-injury, but without exercise), and treated group (LEG-injury and physical exercise). LG and LEG were subjected to sciatic nerve compression with hemostat. From the 3rd day after injury began treatment with exercise, and after 22 days occurs the removal of a nerve fragment for morphological analysis. Results. Regarding allodynia, CG obtained values less than EG (p = 0.012) and larger than LG and LEG (p < 0.001). Histological results showed that CG and EG had normal appearance, as LG and LEG showed up with large amounts of inflammatory infiltration, degeneration and disruption of nerve fibers, and reduction of the myelin sheath; however LEG presented some regenerated fibers. From the morphometric data there were significant differences, for nerve fiber diameter, comparing CG with LG and LEG and comparing axon diameter and the thickness of the myelin of the CG to others. Conclusion. Climb stairs resistance exercise was not effective to speed up the regenerative process of axons. PMID:27594795

  1. Nociceptive and Neuronal Evaluation of the Sciatic Nerve of Wistar Rats Subjected to Compression Injury and Treated with Resistive Exercise

    PubMed Central

    Antunes, Juliana Sobral; Lovison, Keli; Karvat, Jhenifer; Peretti, Ana Luiza; Vieira, Lizyana; Higuchi, Guilherme Hideaki; Ribeiro, Lucinéia de Fátima Chasko

    2016-01-01

    Background. To investigate the climb stairs resistance exercise on nociception and axonal regeneration in the sciatic nerve of rats. Methods. 24 Wistar rats were divided: control group (CG—no injury), exercise group (EG—no injury with physical exercise), lesion group (LG—injury, but without exercise), and treated group (LEG—injury and physical exercise). LG and LEG were subjected to sciatic nerve compression with hemostat. From the 3rd day after injury began treatment with exercise, and after 22 days occurs the removal of a nerve fragment for morphological analysis. Results. Regarding allodynia, CG obtained values less than EG (p = 0.012) and larger than LG and LEG (p < 0.001). Histological results showed that CG and EG had normal appearance, as LG and LEG showed up with large amounts of inflammatory infiltration, degeneration and disruption of nerve fibers, and reduction of the myelin sheath; however LEG presented some regenerated fibers. From the morphometric data there were significant differences, for nerve fiber diameter, comparing CG with LG and LEG and comparing axon diameter and the thickness of the myelin of the CG to others. Conclusion. Climb stairs resistance exercise was not effective to speed up the regenerative process of axons. PMID:27594795

  2. Essential Oil of Ocimum basilicum L. and (-)-Linalool Blocks the Excitability of Rat Sciatic Nerve.

    PubMed

    Medeiros Venancio, Antonio; Ferreira-da-Silva, Francisco Walber; da Silva-Alves, Kerly Shamyra; de Carvalho Pimentel, Hugo; Macêdo Lima, Matheus; Fraga de Santana, Michele; Barreto Alves, Péricles; Batista da Silva, Givanildo; Leal-Cardoso, José Henrique; Marchioro, Murilo

    2016-01-01

    The racemate linalool and its levogyrus enantiomer [(-)-LIN] are present in many essential oils and possess several pharmacological activities, such as antinociceptive and anti-inflammatory. In this work, the effects of essential oil obtained from the cultivation of the Ocimum basilicum L. (EOOb) derived from Germplasm Bank rich in (-)-LIN content in the excitability of peripheral nervous system were studied. We used rat sciatic nerve to investigate the EOOb and (-)-LIN effects on neuron excitability and the extracellular recording technique was used to register the compound action potential (CAP). EOOb and (-)-LIN blocked the CAP in a concentration-dependent way and these effects were reversible after washout. EOOb blocked positive amplitude of 1st and 2nd CAP components with IC50 of 0.38 ± 0.2 and 0.17 ± 0.0 mg/mL, respectively. For (-)-LIN, these values were 0.23 ± 0.0 and 0.13 ± 0.0 mg/mL. Both components reduced the conduction velocity of CAP and the 2nd component seems to be more affected than the 1st component. In conclusion EOOb and (-)-LIN inhibited the excitability of peripheral nervous system in a similar way and potency, revealing that the effects of EOOb on excitability are due to the presence of (-)-LIN in the essential oil.

  3. Microencapsulation improves inhibitory effects of transplanted olfactory ensheathing cells on pain after sciatic nerve injury

    PubMed Central

    Zhao, Hao; Yang, Bao-lin; Liu, Zeng-xu; Yu, Qing; Zhang, Wen-jun; Yuan, Keng; Zeng, Hui-hong; Zhu, Gao-chun; Liu, De-ming; Li, Qing

    2015-01-01

    Olfactory bulb tissue transplantation inhibits P2X2/3 receptor-mediated neuropathic pain. However, the olfactory bulb has a complex cellular composition, and the mechanism underlying the action of purified transplanted olfactory ensheathing cells (OECs) remains unclear. In the present study, we microencapsulated OECs in alginic acid, and transplanted free and microencapsulated OECs into the region surrounding the injured sciatic nerve in rat models of chronic constriction injury. We assessed mechanical nociception in the rat models 7 and 14 days after surgery by measuring paw withdrawal threshold, and examined P2X2/3 receptor expression in L4–5 dorsal root ganglia using immunohistochemistry. Rats that received free and microencapsulated OEC transplants showed greater withdrawal thresholds than untreated model rats, and weaker P2X2/3 receptor immunoreactivity in dorsal root ganglia. At 14 days, paw withdrawal threshold was much higher in the microencapsulated OEC-treated animals. Our results confirm that microencapsulated OEC transplantation suppresses P2X2/3 receptor expression in L4–5 dorsal root ganglia in rat models of neuropathic pain and reduces allodynia, and also suggest that transplantation of microencapsulated OECs is more effective than transplantation of free OECs for the treatment of neuropathic pain. PMID:26487865

  4. Metabolic Dysfunction Is Restricted to the Sciatic Nerve in Experimental Diabetic Neuropathy.

    PubMed

    Freeman, Oliver J; Unwin, Richard D; Dowsey, Andrew W; Begley, Paul; Ali, Sumia; Hollywood, Katherine A; Rustogi, Nitin; Petersen, Rasmus S; Dunn, Warwick B; Cooper, Garth J S; Gardiner, Natalie J

    2016-01-01

    High glucose levels in the peripheral nervous system (PNS) have been implicated in the pathogenesis of diabetic neuropathy (DN). However, our understanding of the molecular mechanisms that cause the marked distal pathology is incomplete. We performed a comprehensive, system-wide analysis of the PNS of a rodent model of DN. We integrated proteomics and metabolomics from the sciatic nerve (SN), the lumbar 4/5 dorsal root ganglia (DRG), and the trigeminal ganglia (TG) of streptozotocin-diabetic and healthy control rats. Even though all tissues showed a dramatic increase in glucose and polyol pathway intermediates in diabetes, a striking upregulation of mitochondrial oxidative phosphorylation and perturbation of lipid metabolism was found in the distal SN that was not present in the corresponding cell bodies of the DRG or the cranial TG. This finding suggests that the most severe molecular consequences of diabetes in the nervous system present in the SN, the region most affected by neuropathy. Such spatial metabolic dysfunction suggests a failure of energy homeostasis and/or oxidative stress, specifically in the distal axon/Schwann cell-rich SN. These data provide a detailed molecular description of the distinct compartmental effects of diabetes on the PNS that could underlie the distal-proximal distribution of pathology. PMID:26470786

  5. Assessment of oxidative parameters in rat spinal cord after chronic constriction of the sciatic nerve.

    PubMed

    Goecks, Cristina S B; Horst, Andréa; Moraes, Maira S; Scheid, Taína; Kolberg, Carolina; Belló-Klein, Adriane; Partata, Wania A

    2012-09-01

    Although reactive oxygen species (ROS) are involved in neuropathic pain, the direct relationship between these species and chronic constriction of sciatic nerve (CCI) has not been studied in spinal cord. Thus, this study induced CCI in rats and these animals were sacrificed 3 and 10 days after the surgical procedure to determine the superoxide dismutase (SOD) and catalase activities, as well as ascorbic acid, hydrogen peroxide (H(2)O(2)) and lipid hydroperoxide levels in lumbosacral spinal cord. Von Frey Hair and hot plate tests were performed to assess the degree of mechanical and thermal hyperalgesia at days 0, 3 and 10. The results showed that CCI significantly induced mechanical and thermal hyperalgesia at days 3 and 10. Parallel there was increase in spinal cord lipid hydroperoxide at days 3 and 10 in rats submitted to CCI. In Sham rats a significant increase in this parameter occurred at day 10. H(2)O(2) decreased at day 10 only in CCI group. SOD activity was decreased in Sham and CCI groups at day 3, while catalase activity was increased in CCI rats at days 3 and 10. Ascorbic acid levels were reduced only in CCI rats at day 3. Although the role of such changes is unclear, many were not specific to neuropathic pain and the differences could be related to different degrees of central sensitization in Sham and CCI rats. PMID:22674084

  6. Essential Oil of Ocimum basilicum L. and (-)-Linalool Blocks the Excitability of Rat Sciatic Nerve.

    PubMed

    Medeiros Venancio, Antonio; Ferreira-da-Silva, Francisco Walber; da Silva-Alves, Kerly Shamyra; de Carvalho Pimentel, Hugo; Macêdo Lima, Matheus; Fraga de Santana, Michele; Barreto Alves, Péricles; Batista da Silva, Givanildo; Leal-Cardoso, José Henrique; Marchioro, Murilo

    2016-01-01

    The racemate linalool and its levogyrus enantiomer [(-)-LIN] are present in many essential oils and possess several pharmacological activities, such as antinociceptive and anti-inflammatory. In this work, the effects of essential oil obtained from the cultivation of the Ocimum basilicum L. (EOOb) derived from Germplasm Bank rich in (-)-LIN content in the excitability of peripheral nervous system were studied. We used rat sciatic nerve to investigate the EOOb and (-)-LIN effects on neuron excitability and the extracellular recording technique was used to register the compound action potential (CAP). EOOb and (-)-LIN blocked the CAP in a concentration-dependent way and these effects were reversible after washout. EOOb blocked positive amplitude of 1st and 2nd CAP components with IC50 of 0.38 ± 0.2 and 0.17 ± 0.0 mg/mL, respectively. For (-)-LIN, these values were 0.23 ± 0.0 and 0.13 ± 0.0 mg/mL. Both components reduced the conduction velocity of CAP and the 2nd component seems to be more affected than the 1st component. In conclusion EOOb and (-)-LIN inhibited the excitability of peripheral nervous system in a similar way and potency, revealing that the effects of EOOb on excitability are due to the presence of (-)-LIN in the essential oil. PMID:27446227

  7. Systemic administration of vitamins C and E attenuates nociception induced by chronic constriction injury of the sciatic nerve in rats.

    PubMed

    Riffel, Ana Paula K; de Souza, Jéssica A; Santos, Maria do Carmo Q; Horst, Andréa; Scheid, Taína; Kolberg, Carolina; Belló-Klein, Adriane; Partata, Wania A

    2016-03-01

    Antioxidants have been tested to treat neuropathic pain, and α-Tocopherol (vitamin E--vit. E) and ascorbic acid (vitamin C--vit. C) are potent antioxidants. We assessed the effect of intraperitoneal administration of vit. C (30 mg/kg/day) and vit. E (15 mg/kg/day), given alone or in combination, on the mechanical and thermal thresholds and the sciatic functional index (SFI) in rats with chronic constriction injury (CCI) of the sciatic nerve. We also determined the lipid hydroperoxides and total antioxidant capacity (TAC) in the injured sciatic nerve. Further, we assessed the effects of oral administration of vit. C+vit. E (vit. C+E) and of a combination of vit. C+E and gabapentin (100mg/kg/day, i.p.) on the mechanical and thermal thresholds of CCI rats. The vitamins, whether administered orally or i.p., attenuated the reductions in the mechanical and thermal thresholds induced by CCI. The antinociceptive effect was greater with a combination of vit. C+E than with each vitamin given alone. The SFI was also improved in vitamin-treated CCI rats. Co-administration of vit. C+E and gabapentin induced a greater antinociceptive effect than gabapentin alone. No significant change occurred in TAC and lipid hydroperoxide levels, but TAC increased (45%) while lipid hydroperoxides decreased (38%) in the sciatic nerve from vit. C+E-treated CCI rats. Thus, treatment with a combination of vit. C+E was more effective to treat CCI-induced neuropathic pain than vitamins alone, and the antinociceptive effect was greater with co-administration of vit. C+E and gabapentin than with gabapentin alone. PMID:26855326

  8. Gene expression microarray analysis of the sciatic nerve of mice with diabetic neuropathy.

    PubMed

    Zhang, Lei; Qu, Shen; Liang, Aibin; Jiang, Hong; Wang, Hao

    2015-02-01

    The present study aimed to explore novel target genes that regulate the development of diabetic neuropathy (DN) by analyzing gene expression profiles in the sciatic nerve of infected mice. The GSE11343 microarray dataset, which was downloaded from Gene Expression Omnibus, included data on 4 control samples and 5 samples from mice with diabetes induced by streptozotocin (STZ), 5 samples from normal mice treated with rosiglitazone (Rosi) and 5 samples from mice with diabetes induced by STZ and treated with Rosi. Differentially expressed genes (DEGs) between the different groups were identified using the substitution augmentation modification redefinition (SAMR) model. The Gene Ontology (GO) term and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed using the Database for Annotation, Visualization and Integrated Discovery (DAVID). Regulatory and protein‑protein interaction networks were searched using BioCarta and STRING, respectively. The protein structures of potential regulatory genes were predicted using the SYBYL program. Compared with the controls, 1,384 DEGs were identified in the mice with STZ-induced diabetes and 7 DEGs were identified in the mice treated with Rosi. There were 518 DEGs identified between the mice in the STZ + Rosi and STZ groups. We identified 45 GO items, and the calmodulin nerve phosphatase and chemokine signaling pathways were identified as the main pathways. Three genes [myristoylated alanine-rich protein kinase C substrate (Marcks), GLI pathogenesis-related 2 (Glipr2) and centrosomal protein 170 kDa (Cep170)] were found to be co-regulated by both STZ and Rosi, the protein structure of which was predicted and certain binding activity to Rosi was docked. Our study demonstrates that the Marcks, Glipr2 and Cep170 genes may be underlying drug targets in the treatment of DN. PMID:25435094

  9. Gene expression microarray analysis of the sciatic nerve of mice with diabetic neuropathy

    PubMed Central

    ZHANG, LEI; QU, SHEN; LIANG, AIBIN; JIANG, HONG; WANG, HAO

    2015-01-01

    The present study aimed to explore novel target genes that regulate the development of diabetic neuropathy (DN) by analyzing gene expression profiles in the sciatic nerve of infected mice. The GSE11343 microarray dataset, which was downloaded from Gene Expression Omnibus, included data on 4 control samples and 5 samples from mice with diabetes induced by streptozotocin (STZ), 5 samples from normal mice treated with rosiglitazone (Rosi) and 5 samples from mice with diabetes induced by STZ and treated with Rosi. Differentially expressed genes (DEGs) between the different groups were identified using the substitution augmentation modification redefinition (SAMR) model. The Gene Ontology (GO) term and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed using the Database for Annotation, Visualization and Integrated Discovery (DAVID). Regulatory and protein-protein interaction networks were searched using BioCarta and STRING, respectively. The protein structures of potential regulatory genes were predicted using the SYBYL program. Compared with the controls, 1,384 DEGs were identified in the mice with STZ-induced diabetes and 7 DEGs were identified in the mice treated with Rosi. There were 518 DEGs identified between the mice in the STZ + Rosi and STZ groups. We identified 45 GO items, and the calmodulin nerve phosphatase and chemokine signaling pathways were identified as the main pathways. Three genes [myristoylated alanine-rich protein kinase C substrate (Marcks), GLI pathogenesis-related 2 (Glipr2) and centrosomal protein 170 kDa (Cep170)] were found to be co-regulated by both STZ and Rosi, the protein structure of which was predicted and certain binding activity to Rosi was docked. Our study demonstrates that the Marcks, Glipr2 and Cep170 genes may be underlying drug targets in the treatment of DN. PMID:25435094

  10. Effect of Platelet Rich Plasma and Platelet Rich Fibrin on sciatic nerve regeneration in a rat model.

    PubMed

    Lichtenfels, Martina; Colomé, Lucas; Sebben, Alessandra Deise; Braga-Silva, Jefferson

    2013-07-01

    The aim of this study was to evaluate the effect of Platelet Rich Plasma (PRP) and Platelet Rich Fibrin (PRF) on peripheral nerve repair. Thirty-two Wistar rats were randomly divided into four equal treatments groups: autologous nerve grafts (ANG), silicon tube plus saline solution (SS), silicon tube plus PRP, and silicon tube plus PRF. In ANG group, 10 mm segment from sciatic nerve was excised and reimplanted between the nerve stumps. In the SS, PRP, and PRF groups, 5 mm segment from sciatic nerve was excised and bridged with a 12 mm silicone conduit to create a 10 mm nerve gap. The conduit was filled in accordance with the different treatments. Walking track analysis was performed periodically and on the 90th post-operative day histomorphometric analysis was performed. The ANG, PRF, and PRP groups presented a significant functional improvement in relation to the SS group (P = 0.001) on 90 days after surgery. Histomorphometric analysis demonstrated that the ANG group achieved a larger nerve fiber diameter in proximal stump while comparing with the SS group (P =0.037) and showed larger fiber diameter in median stump in comparison to the PRP group (P = 0.002) and PRF group (P = 0.001). Axonal diameter and myelin sheath thickness showed no statistical significant difference between the groups in the three stumps (P ≥ 0.05). This study suggests that PRP and PRF have positive effects on the functional nerve recovery; however, these groups don't achieve a significant improvement on the histomorphometric analysis.

  11. Analysis of H2 clearance curves used to measure blood flow in rat sciatic nerve.

    PubMed Central

    Day, T J; Lagerlund, T D; Low, P A

    1989-01-01

    1. By use of the H2 clearance technique, blood flow was measured in the sciatic nerve of healthy, anaesthetized Sprague-Dawley rats at rest, during inferior vena cava occlusion and during 5-hydroxytryptamine infusion. The purpose was to clarify the mechanisms underlying the biexponential curves which are commonly obtained using this technique. 2. An analysis of the frequency distribution of rate constants of 270 nerve and thirty-three arterial samples indicated that H2 clearance rates cluster below 20 ml min-1 100 g-1 and between 70 and 100 ml min-1 100 g-1. This suggests that at least two compartments are present. 3. The contribution of diffusion was studied by recording H2 clearance immediately following circulatory arrest. Slow clearance rates (median = 2.4 ml min-1 100 g-1) were observed, indicating that diffusion is not likely to contribute significantly to nutritive flow under most situations. 4. The contribution of arteriovenous shunts to H2 clearance was assessed by determining H2 clearance during inferior vena cava occlusion and the infusion of 5-hydroxytryptamine. Both manoeuvres caused abolition of, or a significant reduction in the weight of, the fast component which indicates that this compartment is closely related to arteriovenous shunts in nerve. 5. By use of a multi-compartmental model, it was shown that H2 clearance should follow a multi-exponential course, where the weights of the components reflect the relative volumes of each compartment and the exponents represent the relative flow (i.e. flow per unit volume) in each compartment. 6. By use of other mathematical models, estimates were made for the clearance rates attributable to polarographic oxidation of H2 at the tip of the microelectrode (0.2 ml min-1 100 g-1) and to diffusion to air (2 ml min-1 100 g-1). The latter estimate is very close to the measured value of 2.4 ml min-1 100 g-1. 7. These findings indicate that it is possible to separately assess nutritive and non-nutritive flow by

  12. Near-infrared reflectance spectroscopy as a novel method to detect demyelination in rat sciatic nerve in vivo

    NASA Astrophysics Data System (ADS)

    Radhakrishnan, Harsha; Senapati, Arun; Peng, Yuan Bo; Kashyap, Dheerendra; Liu, Hanli

    2005-04-01

    This study was done to use near infrared (NIR) spectroscopy to bring out differences in the anatomical substructures in the rat spinal cord and further to differentiate scattering between demyelinated and normal sciatic nerves in rat models, thereby exploring a new methodology to localize MS (multiple Sclerosis) lesions in vivo for animal studies. The experimental setup consisted of a tungsten light source, CCD array spectrometer, and bifurcated optical fibers for light delivery and detection of back scattered light from tissue. The measurement system was calibrated with reflectance standard. The spinal cord of 14 rats was exposed by laminectomy, and the measurements were taken on 8 points at intervals of 1 mm on the right and left lumbar-sacral regions and the central blood vessel. For measurements on the sciatic nerve, the spinal nerves of 84 rats were ligated according to the Chung Model. Measurements were taken on five points on both the ligated and the control nerve side after 1, 4, 7 and 14 days. The reduced scattering coefficient, μs', was found to be higher in the lumbar-sacral regions (34.17 +/- 2.05 cm-1) than that near the central blood vessel (19.9 +/- 3.8 cm-1). Statistically, there was significant difference in scattering between the control side and the ligated side on postoperative days 4, 7, and 14. This study shows a promising diagnostic value in the future for monitoring of demyelinated CNS (central nervous system) diseases, like Multiple Sclerosis.

  13. The Use of Fiber-Reinforced Scaffolds Cocultured with Schwann Cells and Vascular Endothelial Cells to Repair Rabbit Sciatic Nerve Defect with Vascularization

    PubMed Central

    Gao, Hongyang; You, Yang; Zhang, Guoping; Zhao, Feng; Sha, Ziyi; Shen, Yong

    2013-01-01

    To explore the feasibility of biodegradable fiber-reinforced 3D scaffolds with satisfactory mechanical properties for the repair of long-distance sciatic nerve defect in rabbits and effects of vascularized graft in early stage on the recovery of neurological function, Schwann cells and vascular endothelial cells were cocultured in the fiber-reinforced 3D scaffolds. Experiment group which used prevascularized nerve complex for the repair of sciatic nerve defect and control group which only cultured with Schwann cells were set. The animals in both groups underwent electromyography to show the status of the neurological function recovery at 4, 8, and 16 weeks after the surgery. Sciatic nerve regeneration and myelination were observed under the light microscope and electron microscope. Myelin sheath thickness, axonal diameter, and number of myelinated nerve fiber were quantitatively analyzed using image analysis system. The recovery of foot ulcer, the velocity of nerve conduction, the number of regenerating nerve fiber, and the recovery of ultrastructure were increased in the experimental group than those in the control group. Prevascularized tissue engineered fiber-reinforced 3D scaffolds for the repair of sciatic nerve defects in rabbits can effectively promote the recovery of neurological function. PMID:24490158

  14. Palmitoylethanolamide, a neutraceutical, in nerve compression syndromes: efficacy and safety in sciatic pain and carpal tunnel syndrome

    PubMed Central

    Keppel Hesselink, Jan M; Kopsky, David J

    2015-01-01

    Palmitoylethanolamide (PEA) is an endogenous lipid modulator in animals and humans, and has been evaluated since the 1970s as an anti-inflammatory and analgesic drug in more than 30 clinical trials, in a total of ~6,000 patients. PEA is currently available worldwide as a nutraceutical in different formulations, with and without excipients. Here we describe the results of all clinical trials evaluating PEA’s efficacy and safety in nerve compression syndromes: sciatic pain and pain due to carpal tunnel syndrome, and review preclinical evidence in nerve impingement models. Both the pharmacological studies as well as the clinical trials supported PEA’s action as an analgesic compound. In total, eight clinical trials have been published in such entrapment syndromes, and 1,366 patients have been included in these trials. PEA proved to be effective and safe in nerve compression syndromes. In one pivotal, double blind, placebo controlled trial in 636 sciatic pain patients, the number needed to treat to reach 50% pain reduction compared to baseline was 1.5 after 3 weeks of treatment. Furthermore, no drug interactions or troublesome side effects have been described so far. Physicians are not always aware of PEA as a relevant and safe alternative to opioids and co-analgesics in the treatment of neuropathic pain. Especially since the often prescribed co-analgesic pregabaline has been proven to be ineffective in sciatic pain in a double blind enrichment trial, PEA should be considered as a new and safe treatment option for nerve compression syndromes. PMID:26604814

  15. Gelsemine alleviates both neuropathic pain and sleep disturbance in partial sciatic nerve ligation mice

    PubMed Central

    Wu, Yu-er; Li, Ya-dong; Luo, Yan-jia; Wang, Tian-xiao; Wang, Hui-jing; Chen, Shuo-nan; Qu, Wei-min; Huang, Zhi-li

    2015-01-01

    Aim: Gelsemine, an alkaloid from the Chinese herb Gelsemium elegans (Gardn & Champ) Benth., is effective in mitigating chronic pain in rats. In the present study we investigated whether the alkaloid improved sleep disturbance, the most common comorbid symptoms of chronic pain, in a mouse model of neuropathic pain. Methods: Mice were subjected to partial sciatic nerve ligation (PSNL). After the mice were injected with gelsemine or pregabalin (the positive control) intraperitoneally, mechanical allodynia and thermal hyperalgesia were assessed, and electroencephalogram (EEG)/electromyogram (EMG) recording was performed. Motor performance of the mice was assessed using rota-rod test. c-Fos expression in the brain was analyzed with immunohistochemical staining. Results: In PSNL mice, gelsemine (2 and 4 mg/kg) increased the mechanical threshold for 4 h and prolonged the thermal latencies for 3 h. Furthermore, gelsemine (4 mg/kg, administered at 6:30 AM) increased non-rapid eye movement (non-REM, NREM) sleep, decreased wakefulness, but did not affect REM sleep during the first 3 h in PSNL mice. Sleep architecture analysis showed that gelsemine decreased the mean duration of wakefulness and increased the total number of episodes of NREM sleep during the first 3 h after the dosing. Gelsemine (4 mg/kg) did not impair motor coordination in PSNL mice. Immunohistochemical study showed that PSNL increased c-Fos expression in the neurons of the anterior cingulate cortex, and gelsemine (4 mg/kg) decreased c-Fos expression by 58%. Gelsemine (4 mg/kg, administered at either 6:30 AM or 8:30 PM) did not produce hypnotic effect in normal mice. Pregabalin produced similar antinociceptive and hypnotic effects, but impaired motor coordination in PSNL mice. Conclusion: Gelsemine is an effective agent for treatment of both neuropathic pain and sleep disturbance in PSNL mice; anterior cingulate cortex might play a role in the hypnotic effects of gelsemine. PMID:26388157

  16. Gelatin-methacrylamide gel loaded with microspheres to deliver GDNF in bilayer collagen conduit promoting sciatic nerve growth.

    PubMed

    Zhuang, Hai; Bu, Shoushan; Hua, Lei; Darabi, Mohammad A; Cao, Xiaojian; Xing, Malcolm

    2016-01-01

    In this study, we fabricated glial cell-line derived neurotrophic factor (GDNF)-loaded microspheres, then seeded the microspheres in gelatin-methacrylamide hydrogel, which was finally integrated with the commercial bilayer collagen membrane (Bio-Gide(®)). The novel composite of nerve conduit was employed to bridge a 10 mm long sciatic nerve defect in a rat. GDNF-loaded gelatin microspheres had a smooth surface with an average diameter of 3.9±1.8 μm. Scanning electron microscopy showed that microspheres were uniformly distributed in both the GelMA gel and the layered structure. Using enzyme-linked immunosorbent assay, in vitro release studies (pH 7.4) of GDNF from microspheres exhibited an initial burst release during the first 3 days (18.0%±1.3%), and then, a prolonged-release profile extended to 32 days. However, in an acidic condition (pH 2.5), the initial release percentage of GDNF was up to 91.2%±0.9% within 4 hours and the cumulative release percentage of GDNF was 99.2%±0.2% at 48 hours. Then the composite conduct was implanted in a 10 mm critical defect gap of sciatic nerve in a rat. We found that the nerve was regenerated in both conduit and autograft (AG) groups. A combination of electrophysiological assessment and histomorphometry analysis of regenerated nerves showed that axonal regeneration and functional recovery in collagen tube filled with GDNF-loaded microspheres (GM + CT) group were similar to AG group (P>0.05). Most myelinated nerves were matured and arranged densely with a uniform structure of myelin in a neat pattern along the long axis in the AG and GM + CT groups, however, regenerated nerve was absent in the BLANK group, left the 10 mm gap empty after resection, and the nerve fiber exhibited a disordered arrangement in the collagen tube group. These results indicated that the hybrid system of bilayer collagen conduit and GDNF-loaded gelatin microspheres combined with gelatin-methacrylamide hydrogels could serve as a new biodegradable

  17. Gelatin-methacrylamide gel loaded with microspheres to deliver GDNF in bilayer collagen conduit promoting sciatic nerve growth

    PubMed Central

    Zhuang, Hai; Bu, Shoushan; Hua, Lei; Darabi, Mohammad A; Cao, Xiaojian; Xing, Malcolm

    2016-01-01

    In this study, we fabricated glial cell-line derived neurotrophic factor (GDNF)-loaded microspheres, then seeded the microspheres in gelatin-methacrylamide hydrogel, which was finally integrated with the commercial bilayer collagen membrane (Bio-Gide®). The novel composite of nerve conduit was employed to bridge a 10 mm long sciatic nerve defect in a rat. GDNF-loaded gelatin microspheres had a smooth surface with an average diameter of 3.9±1.8 μm. Scanning electron microscopy showed that microspheres were uniformly distributed in both the GelMA gel and the layered structure. Using enzyme-linked immunosorbent assay, in vitro release studies (pH 7.4) of GDNF from microspheres exhibited an initial burst release during the first 3 days (18.0%±1.3%), and then, a prolonged-release profile extended to 32 days. However, in an acidic condition (pH 2.5), the initial release percentage of GDNF was up to 91.2%±0.9% within 4 hours and the cumulative release percentage of GDNF was 99.2%±0.2% at 48 hours. Then the composite conduct was implanted in a 10 mm critical defect gap of sciatic nerve in a rat. We found that the nerve was regenerated in both conduit and autograft (AG) groups. A combination of electrophysiological assessment and histomorphometry analysis of regenerated nerves showed that axonal regeneration and functional recovery in collagen tube filled with GDNF-loaded microspheres (GM + CT) group were similar to AG group (P>0.05). Most myelinated nerves were matured and arranged densely with a uniform structure of myelin in a neat pattern along the long axis in the AG and GM + CT groups, however, regenerated nerve was absent in the BLANK group, left the 10 mm gap empty after resection, and the nerve fiber exhibited a disordered arrangement in the collagen tube group. These results indicated that the hybrid system of bilayer collagen conduit and GDNF-loaded gelatin microspheres combined with gelatin-methacrylamide hydrogels could serve as a new biodegradable

  18. Release of somatostatin and its role in the mediation of the anti-inflammatory effect induced by antidromic stimulation of sensory fibres of rat sciatic nerve

    PubMed Central

    Szolcsányi, János; Helyes, Zsuzsanna; Oroszi, Gábor; Németh, József; Pintér, Erika

    1998-01-01

    The effect of antidromic stimulation of the sensory fibres of the sciatic nerve on inflammatory plasma extravasation in various tissues and on cutaneous vasodilatation elicited in distant parts of the body was investigated in rats pretreated with guanethidine (8 mg kg−1, i.p.) and pipecuronium (200 μg kg−1, i.v.).Antidromic sciatic nerve stimulation with C-fibre strength (20 V, 0.5 ms) at 5 Hz for 5 min elicited neurogenic inflammation in the innervated area and inhibited by 50.3±4.67% the development of a subsequent plasma extravasation in response to similar stimulation of the contralateral sciatic nerve. Stimulation at 0.5 Hz for 1 h also evoked local plasma extravasation and inhibited the carrageenin-induced (1%, 100 μl s.c.) cutaneous inflammation by 38.5±10.0% in the contralateral paw. Excitation at 0.1 Hz for 4 h elicited no local plasma extravasation in the stimulated hindleg but still reduced the carrageenin-induced oedema by 52.1±9.7% in the paw on the contralateral side.Plasma extravasation in the knee joint in response to carrageenin (2%, 200 μl intra-articular injection) was diminished by 46.1±12.69% and 40.9±4.93% when the sciatic nerve was stimulated in the contralateral leg at 0.5 Hz for 1 h or 0.1 Hz for 4 h, respectively.Stimulation of the peripheral stump of the left vagal nerve (20 V, 1 ms, 8 Hz, 10 min) elicited plasma extravasation in the trachea, oesophagus and mediastinal connective tissue in rats pretreated with atropine (2 mg kg−1, i.v.), guanethidine (8 mg kg−1, i.p.) and pipecuronium (200 μg kg−1, i.v.). These responses were inhibited by 37.8±5.1%, 49.7±9.9% and 37.6±4.2%, respectively by antidromic sciatic nerve excitation (5 Hz, 5 min) applied 5 min earlier.Pretreatment with polyclonal somatostatin antiserum (0.5 ml/rat, i.v.) or the selective somatostatin depleting agent cysteamine (280 mg kg−1, s.c.) prevented the anti-inflammatory effect of

  19. Functional and Physical Outcomes following Use of a Flexible CO2 Laser Fiber and Bipolar Electrocautery in Close Proximity to the Rat Sciatic Nerve with Correlation to an In Vitro Thermal Profile Model

    PubMed Central

    Robinson, A. M.; Fishman, A. J.; Bendok, B. R.; Richter, C.-P.

    2015-01-01

    This study compared functional and physical collateral damage to a nerve when operating a Codman MALIS Bipolar Electrosurgical System CMC-III or a CO2 laser coupled to a laser, with correlation to an in vitro model of heating profiles created by the devices in thermochromic ink agarose. Functional damage of the rat sciatic nerve after operating the MALIS or CO2 laser at various power settings and proximities to the nerve was measured by electrically evoked nerve action potentials, and histology of the nerve was used to assess physical damage. Thermochromic ink dissolved in agarose was used to model the spatial and temporal profile of the collateral heating zone of the electrosurgical system and the laser ablation cone. We found that this laser can be operated at 2 W directly above the nerve with minimal damage, while power settings of 5 W and 10 W resulted in acute functional and physical nerve damage, correlating with the maximal heating cone in the thermochromic ink model. MALIS settings up to 40 (11 W) did not result in major functional or physical nerve damage until the nerve was between the forceps tips, correlating with the hottest zone, localized discretely between the tips. PMID:25699266

  20. Involvement of brain opioid receptors in the anti-allodynic effect of hyperbaric oxygen in rats with sciatic nerve crush-induced neuropathic pain

    PubMed Central

    Gibbons, Carlee R.; Liu, Shulin; Zhang, Yangmiao; Sayre, Casey L.; Levitch, Briana; Moehlmann, Sarah; Shirachi, Donald Y.; Quock, Raymond M.

    2013-01-01

    Earlier research has demonstrated that hyperbaric oxygen (HBO2) can produce an antinociceptive effect in models of acute pain. Recent studies have revealed that HBO2 can produce pain relief in animal models of chronic pain as well. The purpose of the present investigation was to ascertain whether HBO2 treatment might suppress allodynia in rats with neuropathic pain and whether this effect might be blocked by the opioid antagonist naltrexone (NTX). Male Sprague Dawley rats were subjected to a sciatic nerve crush under anesthesia and mechanical thresholds were assessed using an electronic von Frey anesthesiometer. The time course of the HBO2-induced anti-allodynic effect in different treatment groups was plotted, and the area-under-the-curve (AUC) was determined for each group. Seven days after the nerve crush procedure, rats were treated with HBO2 at 3.5 atmospheres absolute (ATA) for 60 min and exhibited an anti-allodynic effect, compared to nerve crush-only control rats. Twenty-four hours before HBO2 treatment, another group of rats was implanted with Alzet® osmotic minipumps that continuously released NTX into the lateral cerebral ventricle for 7 days. These NTX-infused, HBO2-treated rats exhibited an allodynic response comparable to that exhibited by rats receiving nerve crush only. Analysis of the AUC data showed that HBO2 significantly reduced the nerve crush-induced allodynia; this anti-allodynic effect of HBO2 was reversed by NTX. These results implicate opioid receptors in the pain relief induced by HBO2. PMID:23998986

  1. Inhibition of the NMDA receptor protects the rat sciatic nerve against ischemia/reperfusion injury

    PubMed Central

    KE, TIE; LI, RENBIN; CHEN, WENCHANG

    2016-01-01

    Inhibition of the N-methyl-D-aspartate (NMDA) receptor by MK-801 reduces ischemia/reperfusion (I/R) injury in the central nervous system. However, few previous studies have evaluated the neuroprotective effects of MK-801 against peripheral I/R injury. The present study aimed to investigate the protective effects of MK-801 pretreatment against I/R injury in the rat sciatic nerve (SN). Sprague-Dawley rats were subjected to a sham surgery (n=8) or to a 5-h ischemic insult by femoral artery clamping (I/R and I/R+MK-801 groups; n=48 per group). I/R+MK-801 rats were intraperitoneally injected with MK-801 (0.5 ml or 1 mg/kg) at 15 min prior to reperfusion. The rats were sacrificed at 0, 6, 12, 24, 72 h, or 7 days following reperfusion. Plasma malondialdehyde (MDA) and nitric oxide (NO) concentrations, and SN inducible NO synthase (iNOS) protein expression levels, were measured using colorimetry. In addition, the protein expression levels of tumor necrosis factor-α (TNF-α) were measured using immunohistochemistry, and histological analyses of the rat SN were conducted using light and electron microscopy. Alterations in the mRNA expression levels of TNF-α and TNF-α converting enzyme (TACE) in the rat SN were detected using reverse transcription-quantitative polymerase chain reaction. In the I/R group, plasma concentrations of NO (175.3±4.2 µmol/l) and MDA (16.2±1.9 mmol/l), and the levels of iNOS (2.5±0.3) in the SN, peaked at 24 h post-reperfusion. At 24 h, pretreatment with MK-801 significantly reduced plasma NO (107.3±3.6 µmol/l) and MDA (11.8±1.6 mmol/l), and SN iNOS (1.65±0.2) levels (all P<0.01). The mRNA expression levels of TNF-α and TACE in the SN were significantly reduced in the I/R+MK-801 group, as compared with the I/R group (P<0.05). Furthermore, MK-801 pretreatment was shown to have alleviated histological signs of I/R injury, including immune cell infiltration and axon demyelination. The results of the present study suggested that pretreatment

  2. Injury-induced activation of ERK 1/2 in the sciatic nerve of healthy and diabetic rats.

    PubMed

    Stenberg, Lena; Kanje, Martin; Mårtensson, Lisa; Dahlin, Lars B

    2011-01-26

    Phosphorylation of extracellular-signal-regulated kinase 1/2 (p-ERK 1/2) was investigated by immunohistochemistry at 30 min, 1 h, and 48 h after nerve transection in the sciatic nerve of healthy and diabetic [streptozotocin (STZ)-induced diabetes mellitus and BioBreeding (BB; i.e. DR.lyp/lyp or BBDP)] rats. Transection injury increased the intensity of p-ERK 1/2 in nerve stumps at all time points. Staining was confined to Schwann cells with occasional faint staining in single axons. In diabetic rats, a lower intensity of p-ERK 1/2 was found at 1 and 48 h in the distal and proximal nerve stumps compared with healthy rats. STZ-induced diabetic rats were not different from BB rats. p-ERK 1/2 is activated differentially in Schwann cells after nerve injury in diabetic rats, whereas activation in STZ-induced diabetic rats did not differ from BB rats.

  3. Activation of p38 mitogen-activated protein kinase in the early and peak phases of autoimmune neuritis in rat sciatic nerves.

    PubMed

    Moon, Changjong; Ahn, Meejung; Kim, Heechul; Lee, Yongduk; Koh, Chang Sung; Matsumoto, Yoh; Shin, Taekyun

    2005-04-01

    To examine the involvement of p38 mitogen-activated protein kinase (MAPK) in autoimmune disorders of the peripheral nerve system, we analyzed the phosphorylation of p38 MAPK protein in the sciatic nerves of Lewis rats with experimental autoimmune neuritis (EAN). Western blot analysis showed that phosphorylated p38 (p-p38) MAPK protein was significantly increased in the sciatic nerves of rats in the early and peak phases of EAN, and declined gradually thereafter. Immunohistochemistry showed that p-p38 MAPK levels were increased in the infiltrating inflammatory cells, including T cells and macrophages, as well as in blood vessels and some Schwann cells in EAN-affected sciatic nerves, as compared to the sciatic nerves of controls. Some inflammatory cells and a few Schwann cells were also positive for TUNEL reaction at the peak and recovery phases of EAN. In conclusion, we postulate that the phosphorylation of p38 MAPK is involved in the elimination of infiltrating inflammatory cells during the course of EAN and may possibly modulate recovery in autoimmune disorders of the peripheral nervous system.

  4. A new, lateral, continuous, combined, femoral–sciatic nerve approach via a single skin puncture for postoperative analgesia in intramedullary tibial nail insertion

    PubMed Central

    Imbelloni, Luiz Eduardo; Rava, Carlos; Gouveia, Marildo A

    2013-01-01

    Background The prevalence of anterior knee pain following intramedullary tibial nail insertion is high. Continuous peripheral nerve blockade is an alternative method of pain control to opiods. This case illustrates the use of femoral nerve and sciatic nerve peripheral catheters with an elastomeric infusion pump for major intramedullary nailing surgery. Case report A 36-year-old male with fractures to the left leg bones presented for placement of an intramedullary nail under spinal anesthesia. At the end of the procedure, access to the lateral femoral and sciatic continuous nerve block was achieved by using a stimulator connected to a 110 mm 18G Tuohy needle. Postoperative analgesia was provided with a 40-hour infusion of 0.1% bupivacaine (400 mL) at a rate of 10 mL hour−1 with an elastomeric pump. Anesthetic dispersion and contrast were investigated. The analog scale remained with scores below 3 during the 40 hours after surgery, and boluses were not necessary. Conclusion The use of a femoral and sciatic nerve peripheral catheter offered an alternative to conventional pain control. Continuous femoral–sciatic peripheral blockade via a skin puncture with an infusion of 0.1% bupivacaine with elastomeric pumps is a safe and effective procedure in adults. PMID:23630433

  5. Ultrasound-Guided Femoral and Sciatic Nerve Blocks for Repair of Tibia and Fibula Fractures in a Bennett's Wallaby (Macropus rufogriseus)

    PubMed Central

    Campoy, Luis; Adami, Chiara

    2016-01-01

    Locoregional anesthetic techniques may be a very useful tool for the anesthetic management of wallabies with injuries of the pelvic limbs and may help to prevent capture myopathies resulting from stress and systemic opioids' administration. This report describes the use of ultrasound-guided femoral and sciatic nerve blocks in Bennett's wallaby (Macropus rufogriseus) referred for orthopaedic surgery. Ultrasound-guided femoral and sciatic nerve blocks were attempted at the femoral triangle and proximal thigh level, respectively. Whilst the sciatic nerve could be easily visualised, the femoral nerve could not be readily identified. Only the sciatic nerve was therefore blocked with ropivacaine, and methadone was administered as rescue analgesic. The ultrasound images were stored and sent for external review. Anesthesia and recovery were uneventful and the wallaby was discharged two days postoperatively. At the time of writing, it is challenging to provide safe and effective analgesia to Macropods. Detailed knowledge of the anatomy of these species is at the basis of successful locoregional anesthesia. The development of novel analgesic techniques suitable for wallabies would represent an important step forward in this field and help the clinicians dealing with these species to improve their perianesthetic management. PMID:27803817

  6. Myelin ultrastructure of sciatic nerve in rat experimental autoimmune neuritis model and its correlation with associated protein expression

    PubMed Central

    Yuan, Xiao-Jing; Wei, Yu-Jun; Ao, Qiang; Gong, Kai; Wang, Jian-Yong; Sun, Qiang-San; Zhang, Ling; Zheng, Zun-Cheng; Chen, Lin

    2015-01-01

    To explore the relationship of peripheral nerve ultrastructure and its associated protein expression in experimental autoimmune neuritis (EAN). EAN was established in Lewis rats using an emulsified mixture of P0 peptide 180-199, Mycobacterium tuberculosis, and incomplete Freund’s adjuvant. Rats immunized with saline solution were used as a control group. Sciatic nerve ultrastructure and immunofluorescence histopathology were measured at the neuromuscular severity peak on day 18 post-induction. Cell-specific protein markers were used for immunofluorescence histopathology staining to characterize sciatic nerve cells: CD3 (T cell), Iba-1 (microglia), S100 (myelin), and neurofilament 200 (axon). The results showed that swelling of the myelin lamellae, vesicular disorganization, separation of the myelin lamellae, and an attenuation or disappearance of the axon were observed by transmission electron microscopy in the EAN group. CD3 and Iba-1 increased significantly in the structures characterized by separation or swelling of the myelin lamellae, and increased slightly in the structures characterized by vesicular of the myelin lamellae, S100 decreased in the structures characterized by vesicular disorganization or separation of the myelin lamellae. And neurofilament 200 decreased in the structures characterized by separation of the myelin lamellae. Furthermore, we found that Iba1 were positive in the myelin sheath, and overlapped with S100, which significantly indicated that Schwann cells played as macrophage-like cells during the disease progression of ENA. Our findings may be a significant supplement for the knowledge of EAN model, and may offer a novel sight on the treatment of Guillain-Barré syndrome. PMID:26339349

  7. The effect of weight-bearing exercise and non-weight-bearing exercise on gait in rats with sciatic nerve crush injury

    PubMed Central

    Kim, Ki-Hyun; Hwangbo, Gak; Kim, Seong-Gil

    2015-01-01

    [Purpose] The purpose of this study was to access the effect of weight bearing exercise (treadmill exercise) and non-weight-bearing exercise (swimming exercise) on gait in the recovery process after a sciatic nerve crush injury. [Subjects and Methods] Rats were randomly divided into a swimming group (n=3) with non-weight-bearing exercise after a sciatic nerve crush and a treadmill group (n=3) with weight bearing exercise after a sciatic nerve crush. Dartfish is a program that can analyze and interpret motion through video images. The knee lateral epicondyle, lateral malleolus, and metatarsophalangeal joint of the fifth toe were marked by black dots before recording. [Results] There were significant differences in TOK (knee angle toe off) and ICK (knee angle at initial contact) in the swimming group and in TOK, ICA (ankle angle at initial contact), and ICK in the treadmill group. In comparison between groups, there were significant differences in TOA (ankle angle in toe off) and ICA at the 7th day. [Conclusion] There was no difference between weight bearing and non-weight-bearing exercise in sciatic nerve damage, and both exercises accelerated the recovery process in this study. PMID:25995583

  8. Nerve Regeneration in Rat Limb Allografts: Evaluation of Acute Rejection Rescue

    PubMed Central

    Yan, Ying; MacEwan, Matthew R.; Hunter, Daniel A.; Farber, Scott; Newton, Piyaraj; Tung, Thomas H.; Mackinnon, Susan E.; Johnson, Philip J.

    2013-01-01

    Background Successful nerve regeneration is critical to the functional success of composite tissue allografts (CTA). The present study was designed to characterize the effect of acute rejection on nerve regeneration and functional recovery in the setting of orthotopic limb transplantation. Methods A rat orthotopic limb transplantation model was used to evaluate the effects of acute rejection on nerve regeneration and motor recovery. Continuous administration of FK506 (Full suppression), administration of FK506 for the first 8 of 12 weeks (Late rejection), or delayed administration of FK506 / dexamethasone following noticeable rejection (Early rejection) was used to preclude or induce rejection following limb transplantation. Twelve weeks postoperatively, nerve regeneration was assessed via histomorphometric analysis of explanted sciatic nerve, and motor recovery was assessed via evoked muscle force measurement in extensor digitorum longus (EDL) muscle. Results A single episode of acute rejection that occurs immediately or late after reconstruction does not significantly alter the number of regenerating axonal fibers. Acute rejection occurring late after reconstruction adversely affects EDL muscle function in CTA. Conclusion Collected data reinforces that adequate immunosuppressant administration in cases of allogeneic limb transplantation ensures levels of nerve regeneration and motor functional recovery equivalent to that of syngeneic transplants. Prompt rescue following acute rejection was further demonstrated not to significantly affect nerve regeneration and functional recovery post-operatively. However, instances of acute rejection that occur late after reconstruction affect graft function. In total, the present study begins to characterize the effect of immunosuppression regimens on nerve regeneration and motor recovery in the setting of CTA. PMID:23542267

  9. Jinmaitong decreases sciatic nerve DNA oxidative damage and apoptosis in a streptozotocin-induced diabetic rat model

    PubMed Central

    YIN, DE-HAI; LIANG, XIAO-CHUN; ZHAO, LI; ZHANG, HONG; SUN, QING; WANG, PU-YAN; SUN, LIAN-QING

    2015-01-01

    Diabetic peripheral neuropathy (DPN) is a common chronic complication of diabetes. Jinmaitong (JMT), a Traditional Chinese Medicine, improves certain symptoms of DPN, such as limb pain and numbness. The aim of the present study was to investigate the effects of JMT on DNA oxidative damage and apoptosis in the sciatic nerve of diabetic rats. The rats were divided into a normal and a diabetic group. Diabetes was induced using streptozotocin (60 mg/kg). The diabetic model (DM) rats received vitamin C (0.05 g/kg/day) or JMT [low-dosage (L), 0.44 g/kg/day; medium-dosage (M), 0.88 g/kg/day or high-dosage (H), 1.75 g/kg/day]. After 16 weeks, the mechanical pain threshold of the rats was evaluated. The expression of 8-hydroxy-deoxyguanosine (8-OHdG), nicotinamide adenine dinucleotide phosphate (NADPH) oxidase p22phox, B-cell lymphoma 2 (Bcl-2), caspase 3 and cleaved-poly(ADP-ribose) polymerase 1 (PARP-1) in the sciatic nerve tissues was measured using the reverse transcription-quantitative polymerase chain reaction, immunohistochemistry and western blotting. JMT had no effect on body weight and fasting blood glucose levels. Following treatment, the rats in the JMT groups had an improved pain threshold compared with the DM controls (JMT-L, 52.9±6.5 g; JMT-M, 74.7±9.3 g; and JMT-H, 61.7±2.0 g vs. DM control, 35.32±12.06 g; all P<0.01), while the threshold in the JMT-M rats was similar to that of normal controls (P>0.05). 8-OHdG and NADPH oxidase p22phox expression was significantly decreased in the three JMT groups compared with that in the DM controls (all P<0.05). Following JMT treatment, Bcl-2 levels were increased, while caspase 3 and cleaved-PARP-1 levels were decreased compared with those in the DM controls (all P<0.01). In conclusion, JMT may reduce DNA oxidative damage to the sciatic nerve in diabetic rats, as well as regulate genes involved in peripheral neuronal cell apoptosis, suggesting that JMT could be used to prevent or treat DPN in diabetic patients. PMID

  10. Optimal Effect of Phenol Block in the Sciatic Nerve of Rats: Standardization of Minimized Dosage and Duration of Application.

    PubMed

    Lin, Chuan-Chao; Chang, Chein-Wei; Tsai, Su-Ju

    2015-08-31

    The phenol nerve block has been widely used in clinical practice for spasticity reduction, but the correlation between the dosage of phenol and its effectiveness has seldom been discussed. The objective was to determine the optimal duration of phenol in contact with the nervous tissue and to investigate the dose-response relationship of 5% aqueous phenol solution by percutaneous nerve block in rats. Group I (n = 8) received sciatic nerve block by bathing the nerves in phenol solution, and group II (n = 40) by injecting phenol percutaneously. Group IIa to IId received different volumes (0.80, 0.16, 0.08 and 0.04 ml) and group IIe received normal saline. Compound muscle action potential (CMAP) was measured pre-injection and at 90 and 270 sec after injection and after surgical exposure of the nerves. The duration of CMAP reduced by 10%, 25%, 50%, 75% and 100% after phenol injection was also recorded. The mean latency for the evoked response to subside in direct phenol application (group I) and percutaneous nerve block (group IIa) were 73.5 ± 5.9 and 62.4 ± 7.6 sec, respectively. There was no statistical difference for the time periods in the blocking effect elicited by phenol solution between these two methods. Ninety sec was set as the optimal duration for phenol to produce complete conduction blockage. Higher volume of phenol produced more significant blocking effect at 90 and 270 sec after injection. Percutaneous injection with 0.16 ml of phenol solution had the same blocking effect as 0.8 ml. The continuous injection model for percutaneous phenol block indeed used significantly more phenol than actually needed. Clinically, the progressive injection model can be used to minimize injection volume.

  11. Optimal Effect of Phenol Block in the Sciatic Nerve of Rats: Standardization of Minimized Dosage and Duration of Application.

    PubMed

    Lin, Chuan-Chao; Chang, Chein-Wei; Tsai, Su-Ju

    2015-08-31

    The phenol nerve block has been widely used in clinical practice for spasticity reduction, but the correlation between the dosage of phenol and its effectiveness has seldom been discussed. The objective was to determine the optimal duration of phenol in contact with the nervous tissue and to investigate the dose-response relationship of 5% aqueous phenol solution by percutaneous nerve block in rats. Group I (n = 8) received sciatic nerve block by bathing the nerves in phenol solution, and group II (n = 40) by injecting phenol percutaneously. Group IIa to IId received different volumes (0.80, 0.16, 0.08 and 0.04 ml) and group IIe received normal saline. Compound muscle action potential (CMAP) was measured pre-injection and at 90 and 270 sec after injection and after surgical exposure of the nerves. The duration of CMAP reduced by 10%, 25%, 50%, 75% and 100% after phenol injection was also recorded. The mean latency for the evoked response to subside in direct phenol application (group I) and percutaneous nerve block (group IIa) were 73.5 ± 5.9 and 62.4 ± 7.6 sec, respectively. There was no statistical difference for the time periods in the blocking effect elicited by phenol solution between these two methods. Ninety sec was set as the optimal duration for phenol to produce complete conduction blockage. Higher volume of phenol produced more significant blocking effect at 90 and 270 sec after injection. Percutaneous injection with 0.16 ml of phenol solution had the same blocking effect as 0.8 ml. The continuous injection model for percutaneous phenol block indeed used significantly more phenol than actually needed. Clinically, the progressive injection model can be used to minimize injection volume. PMID:26211647

  12. Dorsal root ganglion-derived Schwann cells combined with poly(lactic-co-glycolic acid)/chitosan conduits for the repair of sciatic nerve defects in rats.

    PubMed

    Zhao, Li; Qu, Wei; Wu, Yuxuan; Ma, Hao; Jiang, Huajun

    2014-11-15

    Schwann cells, nerve regeneration promoters in peripheral nerve tissue engineering, can be used to repair both the peripheral and central nervous systems. However, isolation and purification of Schwann cells are complicated by contamination with fibroblasts. Current reported measures are mainly limited by either high cost or complicated procedures with low cell yields or purity. In this study, we collected dorsal root ganglia from neonatal rats from which we obtained highly purified Schwann cells using serum-free melanocyte culture medium. The purity of Schwann cells (> 95%) using our method was higher than that using standard medium containing fetal bovine serum. The obtained Schwann cells were implanted into poly(lactic-co-glycolic acid)/chitosan conduits to repair 10-mm sciatic nerve defects in rats. Results showed that axonal diameter and area were significantly increased and motor functions were obviously improved in the rat sciatic nerve tissue. Experimental findings suggest that serum-free melanocyte culture medium is conducive to purify Schwann cells and poly(lactic-co-glycolic acid)/chitosan nerve conduits combined with Schwann cells contribute to restore sciatic nerve defects.

  13. Gabapentin Treatment for Neuropathic Pain in a Child with Sciatic Nerve Injury

    PubMed Central

    Akkurt, Halil Ekrem; Gümüş, Haluk; Göksu, Hamit; Odabaşı, Ömer Faruk; Yılmaz, Halim

    2015-01-01

    There are a restricted number of studies about usage of gabapentin for neuropathic pain treatment of pediatric patients. We shared a 12-year-old male case with severe neuropathic pain that hindered the rehabilitation programme for the loss of muscle power and movement limitation. Neuropathic pain developed after peripheral sciatic damage due to firearm traumatisation did not respond to other medical treatments but healed nearly completely after gabapentin usage. PMID:26346828

  14. Impairment of cytoskeletal protein transport due to aging or beta,beta'-iminodipropionitrile intoxication in the rat sciatic nerve.

    PubMed

    Tashiro, T; Komiya, Y

    1994-01-01

    Three major age-related changes in cytoskeletal organization and metabolism in the axon were observed by comparing slow axonal transport in the sciatic nerves of rats aged 7-80 weeks: (a) a progressive decrease in the rate of slow axonal transport, (b) a tight association of cold-insoluble tubulin with the neurofilament (NF) proteins and (c) an accelerated proteolysis of the severely retarded proteins, especially NF proteins. These changes were reproduced to a large extent in the young animal by intoxication with beta,beta'-iminodipropionitrile (IDPN). As IDPN is known to impair the axonal transport of NF proteins and cause segregation of NFs from microtubules, the results indicate that NF-microtubule interaction is one of the major factors regulating the axonal cytoskeleton. The importance of the balance between transport rate and degradation rate in the maintenance of the normal axonal cytoskeleton is stressed especially in the aged animal.

  15. Preliminary Investigation on Use of High-Resolution Optical Coherence Tomography to Monitor Injury and Repair in the Rat Sciatic Nerve

    PubMed Central

    Chlebicki, Cara A.; Lee, Alice D.; Jung, Woonggyu; Li, Hongrui; Liaw, Lih-Huei; Chen, Zhongping; Wong, Brian J.

    2010-01-01

    Background and Objective Optical coherence tomography (OCT) has been used in limited settings to study peripheral nerve injury. The purpose of the study is to determine whether high-resolution OCT can be used to monitor nerve injury and regeneration in the rat sciatic nerve following crush injury, ligation, and transection with microsurgical repair. Study Design/Materials and Methods Forty-five rats were segregated into three groups. The right sciatic nerve was suture ligated (n = 15), cut then microsurgically repaired (n = 15), or crushed (n = 15). The left sciatic nerve served as the control; only surgical exposure and skin closure were performed. Each group was further divided into three subgroups where they were assigned survival durations of 4, 15, or 24 weeks. Following euthanasia, nerves were harvested, fixed in formalin, and imaged at the injury site, as well as proximal and distal ends. The OCT system resolution was approximately 7 μm in tissue with a 1,060 nm central wavelength. Results Control (uninjured) nerve tissue showed homogenous signal distribution to a relatively uniform depth; in contrast, damaged nerves showed irregular signal distribution and intensity. Changes in signal distribution were most significant at the injury site and distal regions. Increases in signal irregularity were evident during longer recovery times. Histological analysis determined that OCT imaging was limited to the surrounding perineurium and scar tissue. Conclusion OCT has the potential to be a valuable tool for monitoring nerve injury and repair, and the changes that accompany wound healing, providing clinicians with a non-invasive tool to treat nerve injuries. PMID:20432279

  16. Behavioral and cellular consequences of high-electrode count Utah Arrays chronically implanted in rat sciatic nerve

    NASA Astrophysics Data System (ADS)

    Wark, H. A. C.; Mathews, K. S.; Normann, R. A.; Fernandez, E.

    2014-08-01

    Objective. Before peripheral nerve electrodes can be used for the restoration of sensory and motor functions in patients with neurological disorders, the behavioral and histological consequences of these devices must be investigated. These indices of biocompatibility can be defined in terms of desired functional outcomes; for example, a device may be considered for use as a therapeutic intervention if the implanted subject retains functional neurons post-implantation even in the presence of a foreign body response. The consequences of an indwelling device may remain localized to cellular responses at the device-tissue interface, such as fibrotic encapsulation of the device, or they may affect the animal more globally, such as impacting behavioral or sensorimotor functions. The objective of this study was to investigate the overall consequences of implantation of high-electrode count intrafascicular peripheral nerve arrays, High Density Utah Slanted Electrode Arrays (HD-USEAs; 25 electrodes mm-2). Approach. HD-USEAs were implanted in rat sciatic nerves for one and two month periods. We monitored wheel running, noxious sensory paw withdrawal reflexes, footprints, nerve morphology and macrophage presence at the tissue-device interface. In addition, we used a novel approach to contain the arrays in actively behaving animals that consisted of an organic nerve wrap. A total of 500 electrodes were implanted across all ten animals. Main results. The results demonstrated that chronic implantation (⩽8 weeks) of HD-USEAs into peripheral nerves can evoke behavioral deficits that recover over time. Morphology of the nerve distal to the implantation site showed variable signs of nerve fiber degeneration and regeneration. Cytology adjacent to the device-tissue interface also showed a variable response, with some electrodes having many macrophages surrounding the electrodes, while other electrodes had few or no macrophages present. This variability was also seen along the length

  17. MHC-I and PirB Upregulation in the Central and Peripheral Nervous System following Sciatic Nerve Injury.

    PubMed

    Bombeiro, André Luis; Thomé, Rodolfo; Oliveira Nunes, Sérgio Luiz; Monteiro Moreira, Bárbara; Verinaud, Liana; Oliveira, Alexandre Leite Rodrigues de

    2016-01-01

    Major histocompatibility complex class one (MHC-I) antigen-presenting molecules participate in central nervous system (CNS) synaptic plasticity, as does the paired immunoglobulin-like receptor B (PirB), an MHC-I ligand that can inhibit immune-cells and bind to myelin axon growth inhibitors. Based on the dual roles of both molecules in the immune and nervous systems, we evaluated their expression in the central and peripheral nervous system (PNS) following sciatic nerve injury in mice. Increased PirB and MHC-I protein and gene expression is present in the spinal cord one week after nerve transection, PirB being mostly expressed in the neuropile region. In the crushed nerve, MHC-I protein levels increased 2 weeks after lesion (wal) and progressively decreased over the next eight weeks. The same kinetics were observed for infiltrating cytotoxic T lymphocytes (CTLs) but not for PirB expression, which continuously increased. Both MHC-I and PirB were found in macrophages and Schwann cells but rarely in axons. Interestingly, at 8 wal, PirB was mainly restricted to the myelin sheath. Our findings reinforce the participation of MHC-I and PirB in CNS plasticity events. In contrast, opposing expression levels of these molecules were found in the PNS, so that MHC-I and PirB seem to be mostly implicated in antigen presentation to CTLs and axon myelination, respectively. PMID:27551751

  18. MHC-I and PirB Upregulation in the Central and Peripheral Nervous System following Sciatic Nerve Injury

    PubMed Central

    Bombeiro, André Luis; Thomé, Rodolfo; Oliveira Nunes, Sérgio Luiz; Monteiro Moreira, Bárbara; Verinaud, Liana; de Oliveira, Alexandre Leite Rodrigues

    2016-01-01

    Major histocompatibility complex class one (MHC-I) antigen-presenting molecules participate in central nervous system (CNS) synaptic plasticity, as does the paired immunoglobulin-like receptor B (PirB), an MHC-I ligand that can inhibit immune-cells and bind to myelin axon growth inhibitors. Based on the dual roles of both molecules in the immune and nervous systems, we evaluated their expression in the central and peripheral nervous system (PNS) following sciatic nerve injury in mice. Increased PirB and MHC-I protein and gene expression is present in the spinal cord one week after nerve transection, PirB being mostly expressed in the neuropile region. In the crushed nerve, MHC-I protein levels increased 2 weeks after lesion (wal) and progressively decreased over the next eight weeks. The same kinetics were observed for infiltrating cytotoxic T lymphocytes (CTLs) but not for PirB expression, which continuously increased. Both MHC-I and PirB were found in macrophages and Schwann cells but rarely in axons. Interestingly, at 8 wal, PirB was mainly restricted to the myelin sheath. Our findings reinforce the participation of MHC-I and PirB in CNS plasticity events. In contrast, opposing expression levels of these molecules were found in the PNS, so that MHC-I and PirB seem to be mostly implicated in antigen presentation to CTLs and axon myelination, respectively. PMID:27551751

  19. Injury-Dependent and Disability-Specific Lumbar Spinal Gene Regulation following Sciatic Nerve Injury in the Rat.

    PubMed

    Austin, Paul J; Bembrick, Alison L; Denyer, Gareth S; Keay, Kevin A

    2015-01-01

    Allodynia, hyperalgesia and spontaneous pain are cardinal sensory signs of neuropathic pain. Clinically, many neuropathic pain patients experience affective-motivational state changes, including reduced familial and social interactions, decreased motivation, anhedonia and depression which are severely debilitating. In earlier studies we have shown that sciatic nerve chronic constriction injury (CCI) disrupts social interactions, sleep-wake-cycle and endocrine function in one third of rats, a subgroup reliably identified six days after injury. CCI consistently produces allodynia and hyperalgesia, the intensity of which was unrelated either to the altered social interactions, sleep-wake-cycle or endocrine changes. This decoupling of the sensory consequences of nerve injury from the affective-motivational changes is reported in both animal experiments and human clinical data. The sensory changes triggered by CCI are mediated primarily by functional changes in the lumbar dorsal horn, however, whether lumbar spinal changes may drive different affective-motivational states has never been considered. In these studies, we used microarrays to identify the unique transcriptomes of rats with altered social behaviours following sciatic CCI to determine whether specific patterns of lumbar spinal adaptations characterised this subgroup. Rats underwent CCI and on the basis of reductions in dominance behaviour in resident-intruder social interactions were categorised as having Pain & Disability, Pain & Transient Disability or Pain alone. We examined the lumbar spinal transcriptomes two and six days after CCI. Fifty-four 'disability-specific' genes were identified. Sixty-five percent were unique to Pain & Disability rats, two-thirds of which were associated with neurotransmission, inflammation and/or cellular stress. In contrast, 40% of genes differentially regulated in rats without disabilities were involved with more general homeostatic processes (cellular structure

  20. Injury-Dependent and Disability-Specific Lumbar Spinal Gene Regulation following Sciatic Nerve Injury in the Rat

    PubMed Central

    Denyer, Gareth S.; Keay, Kevin A.

    2015-01-01

    Allodynia, hyperalgesia and spontaneous pain are cardinal sensory signs of neuropathic pain. Clinically, many neuropathic pain patients experience affective-motivational state changes, including reduced familial and social interactions, decreased motivation, anhedonia and depression which are severely debilitating. In earlier studies we have shown that sciatic nerve chronic constriction injury (CCI) disrupts social interactions, sleep-wake-cycle and endocrine function in one third of rats, a subgroup reliably identified six days after injury. CCI consistently produces allodynia and hyperalgesia, the intensity of which was unrelated either to the altered social interactions, sleep-wake-cycle or endocrine changes. This decoupling of the sensory consequences of nerve injury from the affective-motivational changes is reported in both animal experiments and human clinical data. The sensory changes triggered by CCI are mediated primarily by functional changes in the lumbar dorsal horn, however, whether lumbar spinal changes may drive different affective-motivational states has never been considered. In these studies, we used microarrays to identify the unique transcriptomes of rats with altered social behaviours following sciatic CCI to determine whether specific patterns of lumbar spinal adaptations characterised this subgroup. Rats underwent CCI and on the basis of reductions in dominance behaviour in resident-intruder social interactions were categorised as having Pain & Disability, Pain & Transient Disability or Pain alone. We examined the lumbar spinal transcriptomes two and six days after CCI. Fifty-four ‘disability-specific’ genes were identified. Sixty-five percent were unique to Pain & Disability rats, two-thirds of which were associated with neurotransmission, inflammation and/or cellular stress. In contrast, 40% of genes differentially regulated in rats without disabilities were involved with more general homeostatic processes (cellular structure

  1. Spatiotemporal characteristics of cerebral blood volume changes in different microvascular compartments evoked by sciatic nerve stimulation in rat somatosensory cortex

    NASA Astrophysics Data System (ADS)

    Li, Pengcheng; Luo, Qingming; Luo, Weihua; Chen, Shanbin; Cheng, Haiying; Zeng, Shaoqun

    2003-07-01

    The spatio-temporal characteristics of changes in cerebral blood volume associated with neuronal activity were investigated in the hindlimb somatosensory cortex of α-chloralose/urethan anesthetized rats (n=10) with optical imaging at 570nm through a thinned skull. Activation of cortex was carried out by electrical stimulation of the contralateral sciatic nerve with 5Hz, 0.3V pulses (0.5ms) for duration of 2s. The stimulation evoked a monophasic optical reflectance decrease at cortical parenchyma and arteries sites rapidly after the onset of stimulation, whereas no similar response was observed at vein compartments. The optical signal changes reached 10% of the peak response 0.70+/-0.32s after stimulation onset and no significant time lag in this 10% start latency time was observed between the response at cortical parenchyma and arteries compartments. The evoked optical reflectance decrease reached the peak (0.25%+/-0.047%) 2.66+/-0.61s after the stimulus onset at parenchyma site, 0.40+/-0.20s earlier (P<0.05) than that at arteries site (0.50+/-0.068% 3.06+/-0.70s). Variable location within the cortical parenchyma and arteries compartment themselves didn"t affect the temporal characteristics of the evoked signal significantly. These results suggest that the sciatic nerve stimulation evokes a local blood volume increase at both capillaries (cortical parenchyma) and arterioles rapidly after the stimulus onset but the evoked blood volume increase in capillaries could not be entirely accounted for by the dilation of arterioles.

  2. Hybrid electro-optical stimulation of the rat sciatic nerve induces force generation in the plantarflexor muscles

    NASA Astrophysics Data System (ADS)

    Duke, Austin R.; Peterson, Erik; Mackanos, Mark A.; Atkinson, James; Tyler, Dustin; Jansen, E. Duco

    2012-12-01

    Objective. Optical methods of neural activation are becoming important tools for the study and treatment of neurological disorders. Infrared nerve stimulation (INS) is an optical technique exhibiting spatially precise activation in the native neural system. While this technique shows great promise, the risk of thermal damage may limit some applications. Combining INS with traditional electrical stimulation, a method known as hybrid electro-optical stimulation, reduces the laser power requirements and mitigates the risk of thermal damage while maintaining spatial selectivity. Here we investigate the capability of inducing force generation in the rat hind limb through hybrid stimulation of the sciatic nerve. Approach. Hybrid stimulation was achieved by combining an optically transparent nerve cuff for electrical stimulation and a diode laser coupled to an optical fiber for infrared stimulation. Force generation in the rat plantarflexor muscles was measured in response to hybrid stimulation with 1 s bursts of pulses at 15 and 20 Hz and with a burst frequency of 0.5 Hz. Main results. Forces were found to increase with successive stimulus trains, ultimately reaching a plateau by the 20th train. Hybrid evoked forces decayed at a rate similar to the rate of thermal diffusion in tissue. Preconditioning the nerve with an optical stimulus resulted in an increase in the force response to both electrical and hybrid stimulation. Histological evaluation showed no signs of thermally induced morphological changes following hybrid stimulation. Our results indicate that an increase in baseline temperature is a likely contributor to hybrid force generation. Significance. Extraneural INS of peripheral nerves at physiologically relevant repetition rates is possible using hybrid electro-optical stimulation.

  3. Up-regulated uridine kinase gene identified by RLCS in the ventral horn after crush injury to rat sciatic nerves.

    PubMed

    Yuh, I; Yaoi, T; Watanabe, S; Okajima, S; Hirasawa, Y; Fushiki, S

    1999-12-01

    Rat sciatic nerve crush injury is one of the models commonly employed for studying the mechanisms of nerve regeneration. In this study, we analyzed the temporal change of gene expression after injury in this model, to elucidate the molecular mechanisms involved in nerve regeneration. First, a cDNA analysis method, Restriction Landmark cDNA Scanning (RLCS), was applied to cells in the ventral horn of the spinal cord during a 7-day period after the crush injury. A total of 1991 cDNA species were detected as spots on gels, and 37 of these were shown to change after the injury. Temporally changed patterns were classified into three categories: the continuously up-regulated type (10 species), the transiently up-regulated type (22 species), and the down-regulated type (5 species). These complex patterns of gene expression demonstrated after the injury suggest that precise regulation in molecular pathways is required for accomplishing nerve regeneration. Secondly, the rat homologue of uridine kinase gene was identified as one of the up-regulated genes. Northern blot analysis on rat ventral horn tissue and brain revealed that the UK gene had three transcripts with different sizes (4.3, 1. 4, and 1.35 kb, respectively). All of the transcripts, especially the 4.3 kb one, were up-regulated mainly in a bimodal fashion during the 28-day period after the injury. The RLCS method that we employed in the present study shows promise as a means to fully analyze molecular changes in nerve regeneration in detail. PMID:10581173

  4. Characteristics of sympathetic nerve activity in the rat sciatic nerve in response to microstimulation in a sympathetic fascicle in the contralateral side.

    PubMed

    Sato, Daisuke; Shiwaku, Yutaka; Nakamura, Ryoichi; Koizumi, Shuntaro; Feng, Zhonggang; Kusunoki, Masataka; Nakamura, Takao

    2013-01-01

    Microneurography is used for the monitor of various peripheral nerve activities. We recently reported that the electrical stimulation of peripheral sympathetic nerve fascicle via the microelectrode, i.e., microstimulation, temporarily reduced the blood glucose level in rats in case that the stimulation intensity was set high enough to induce small muscle contraction. However, the nature of microstimulation has little been clarified yet. Therefore, in the present study, we first detected sympathetic nerve signal microneurographically in the bilateral sciatic nerves of rats, and one of the microelectrodes was used for the microstimulation (0.25 ms-width pulse train at a rate of 1 Hz) while sympathetic nerve activity (SNA) was recorded in the contralateral side as a parameter of systemic sympathetic effects. The SNA, expressed as action potential rate, was transiently increased 150 ms after each stimulation pulse in case that the stimulation intensity was set not less than -0.1 V from the contraction threshold (around 0.32 V). To confirm that the increase was not caused by the activation of low threshold, thick fibers such as motor nerves in the vicinity of the microelectrode tip, next, a bipolar hook electrode, instead of the microelectrode, was then used in the stimulation side. As a result, the above-mentioned, transient increase in SNA was not observed any more in the contralateral side. These results suggest that systemic SNA could be enhanced with lower stimulation intensity than that inducing muscle contraction, and that thicker fibers may little affect the increase in the contralateral SNA. PMID:24111188

  5. The morphological and functional effects of exercise in the aquatic environment, performed before and/or after sciatic nerve compression in Wistar rats

    PubMed Central

    Kakihata, Camila Mayumi Martin; Malanotte, Jéssica Aline; Karvat, Jhenifer; Brancalhão, Rose Meire Costa; de Fátima Chasko Ribeiro, Lucinéia; Bertolini, Gladson Ricardo Flor

    2016-01-01

    The aim of this study was to evaluate the effects of exercise in the aquatic environment, performed before and/or after sciatic nerve compression in Wistar rats on morphological and functional parameters. Twenty-five Wistar rats were divided into the following groups: control (C), lesion (L), trained+lesion (TL), lesion+exercise (LE), and training+lesion+exercise (TLE), who underwent right sciatic nerve compression on day 21 of the experiment. The TL and TLE groups were submitted to a jumping exercise in a water environment for 20 days prior to injury and the LE and TLE groups after injury. The functional analysis was carried out using the sciatic functional index (SFI). On the last day of the experiment, the right sciatic nerves were collected, processed and analysed according to morphology and morphometry. The C group showed higher SFI in relation to the other groups. In the morphometric analysis, in comparison to C, all groups showed a decrease in the diameter of the injured nerve fibre, the myelin sheath and an increase in the percentage of connective tissue. There was a decrease in axon diameter in L, TL, and LE groups and a decrease in the density of nerve fibres in the TL and LE groups. The exercise did not affect functional recovery. However, the exercise prior to the injury improved morphology of the nervous tissue, and when performed pre- and postinjury, there was also an improvement in nerve regeneration, but this was not the case with exercise performed after the injury demonstrating worse results. PMID:27807516

  6. Sciatic nerve regeneration induced by transplantation of in vitro bone marrow stromal cells into an inside-out artery graft in rat.

    PubMed

    Mohammadi, Rahim; Vahabzadeh, Behnam; Amini, Keyvan

    2014-10-01

    Traumatic injury to peripheral nerves results in considerable motor and sensory disability. Several research groups have tried to improve the regeneration of traumatized nerves by invention of favorable microsurgery. Effect of undifferentiated bone marrow stromal cells (BMSCs) combined with artery graft on peripheral nerve regeneration was studied using a rat sciatic nerve regeneration model. A 10-mm sciatic nerve defect was bridged using an artery graft (IOAG) filled with undifferentiated BMSCs (2 × 10(7) cells/mL). In control group, the graft was filled with phosphated buffer saline alone. The regenerated fibers were studied 4, 8 and 12 weeks after surgery. Assessment of nerve regeneration was based on behavioral, functional (Walking Track Analysis), electrophysiological, histomorphometric and immuohistochemical (Schwann cell detection by S-100 expression) criteria. The behavioral, functional and electrophysiological studies confirmed significant recovery of regenerated axons in IOAG/BMSC group (P < 0.05). Quantitative morphometric analyses of regenerated fibers showed the number and diameter of myelinated fibers in IOAG/BMSC group were significantly higher than in the control group (P < 0.05). This demonstrates the potential of using undifferentiated BMSCs combined with artery graft in peripheral nerve regeneration without limitations of donor-site morbidity associated with isolation of Schwann cells. It is also cost saving due to reduction in interval from tissue collection until cell injection, simplicity of laboratory procedures compared to differentiated BMSCs and may have clinical implications for the surgical management of patients after facial nerve transection. PMID:24942097

  7. The parameters of transcutaneous electrical nerve stimulation are critical to its regenerative effects when applied just after a sciatic crush lesion in mice.

    PubMed

    Cavalcante Miranda de Assis, Diana; Martins Lima, Êmyle; Teixeira Goes, Bruno; Zugaib Cavalcanti, João; Barbosa Paixão, Alaí; Vannier-Santos, Marcos André; Martinez, Ana Maria Blanco; Baptista, Abrahão Fontes

    2014-01-01

    We investigated the effect of two frequencies of transcutaneous electrical nerve stimulation (TENS) applied immediately after lesion on peripheral nerve regeneration after a mouse sciatic crush injury. The animals were anesthetized and subjected to crushing of the right sciatic nerve and then separated into three groups: nontreated, Low-TENS (4 Hz), and High-TENS (100 Hz). The animals of Low- and High-TENS groups were stimulated for 2 h immediately after the surgical procedure, while the nontreated group was only positioned for the same period. After five weeks the animals were euthanized, and the nerves dissected bilaterally for histological and histomorphometric analysis. Histological assessment by light and electron microscopy showed that High-TENS and nontreated nerves had a similar profile, with extensive signs of degeneration. Conversely, Low-TENS led to increased regeneration, displaying histological aspects similar to control nerves. High-TENS also led to decreased density of fibers in the range of 6-12 μm diameter and decreased fiber diameter and myelin area in the range of 0-2 μm diameter. These findings suggest that High-TENS applied just after a peripheral nerve crush may be deleterious for regeneration, whereas Low-TENS may increase nerve regeneration capacity.

  8. Effect of Treating Streptozotocin-Induced Diabetic Rats With Sorbinil, Myo-Inositol or Aminoguanidine on Endoneurial Blood Flow, Motor Nerve Conduction Velocity and Vascular Function of Epineurial Arterioles of the Sciatic Nerve

    PubMed Central

    Coppey, Lawrence J.; Gellett, Jill S.; Davidson, Eric P.; Dunlap, Joyce A.

    2002-01-01

    Previously we have demonstrated that diabetes causes impairment in vascular function of epineurial vessels, which precedes the slowing of motor nerve conduction velocity. Treatment of diabetic rats with aldose reductase inhibitors, aminoguanidine or myo-inositol supplementation have been shown to improve motor nerve conduction velocity and/or decreased endoneurial blood flow. However, the effect these treatments have on vascular reactivity of epineurial vessels of the sciatic nerve is unknown. In these studies we examined the effect of treating streptozotocininduced rats with sorbinil, aminoguanidine or myo-inositol on motor nerve conduction velocity, endoneurial blood flow and endothelium dependent vascular relaxation of arterioles that provide circulation to the region of the sciatic nerve. Treating diabetic rats with sorbinil, aminoguanidine or myo-inositol improved the reduction of endoneurial blood flow and motor nerve conduction velocity. However, only sorbinil treatment significantly improved the diabetes-induced impairment of acetylcholinemediated vasodilation of epineurial vessels of the sciatic nerve. All three treatments were efficacious in preventing the appropriate metabolic derangements associated with either activation of the polyol pathway or increased nonenzymatic glycation. In addition, sorbinil was shown to prevent the diabetes-induced decrease in lens glutathione level. However, other markers of oxidative stress were not vividly improved by these treatments. These studies suggest that sorbinil treatment may be more effective in preventing neural dysfunction in diabetes than either aminoguanidine or myoinositol. PMID:11900277

  9. Inhibition of the compound action potentials of frog sciatic nerves by aroma oil compounds having various chemical structures

    PubMed Central

    Ohtsubo, Sena; Fujita, Tsugumi; Matsushita, Akitomo; Kumamoto, Eiichi

    2015-01-01

    Plant-derived chemicals including aroma oil compounds have an ability to inhibit nerve conduction and modulate transient receptor potential (TRP) channels. Although applying aroma oils to the skin produces a local anesthetic effect, this has not been yet examined throughly. The aim of the present study was to know how nerve conduction inhibitions by aroma oil compounds are related to their chemical structures and whether these activities are mediated by TRP activation. Compound action potentials (CAPs) were recorded from the frog sciatic nerve by using the air-gap method. Citral (aldehyde), which activates various types of TRP channels, attenuated the peak amplitude of CAP with the half-maximal inhibitory concentration (IC50) value of 0.46 mmol/L. Another aldehyde (citronellal), alcohol (citronellol, geraniol, (±)-linalool, (−)-linalool, (+)-borneol, (−)-borneol, α-terpineol), ester (geranyl acetate, linalyl acetate, bornyl acetate), and oxide (rose oxide) compounds also reduced CAP peak amplitudes (IC50: 0.50, 0.35, 0.53, 1.7, 2.0, 1.5, 2.3, 2.7, 0.51, 0.71, 0.44, and 2.6 mmol/L, respectively). On the other hand, the amplitudes were reduced by a small extent by hydrocarbons (myrcene and p-cymene) and ketone (camphor) at high concentrations (2–5 mmol/L). The activities of citral and other TRP agonists ((+)-borneol and camphor) were resistant to TRP antagonist ruthenium red. An efficacy sequence for the CAP inhibitions was generally aldehydes ≥ esters ≥ alcohols > oxides >> hydrocarbons. The CAP inhibition by the aroma oil compound was not related to its octanol–water partition coefficient. It is suggested that aroma oil compounds inhibit nerve conduction in a manner specific to their chemical structures without TRP activation. PMID:26038703

  10. Bortezomib Treatment Produces Nocifensive Behavior and Changes in the Expression of TRPV1, CGRP, and Substance P in the Rat DRG, Spinal Cord, and Sciatic Nerve

    PubMed Central

    Quartu, M.; Carozzi, V. A.; Dorsey, S. G.; Serra, M. P.; Poddighe, L.; Picci, C.; Boi, M.; Melis, T.; Del Fiacco, M.; Meregalli, C.; Chiorazzi, A.; Renn, C. L.; Cavaletti, G.; Marmiroli, P.

    2014-01-01

    To investigate neurochemical changes associated with bortezomib-induced painful peripheral neuropathy (PN), we examined the effects of a single-dose intravenous administration of bortezomib and a well-established “chronic” schedule in a rat model of bortezomib-induced PN. The TRPV1 channel and sensory neuropeptides CGRP and substance P (SP) were studied in L4-L5 dorsal root ganglia (DRGs), spinal cord, and sciatic nerve. Behavioral measures, performed at the end of the chronic bortezomib treatment, confirmed a reduction of mechanical nociceptive threshold, whereas no difference occurred in thermal withdrawal latency. Western blot analysis showed a relative increase of TRPV1 in DRG and spinal cord after both acute and chronic bortezomib administration. Reverse transcriptase-polymerase chain reaction revealed a decrease of TRPV1 and CGRP mRNA relative levels after chronic treatment. Immunohistochemistry showed that in the DRGs, TRPV1-, CGRP-, and SP-immunoreactive neurons were mostly small- and medium-sized and the proportion of TRPV1- and CGRP-labeled neurons increased after treatment. A bortezomib-induced increase in density of TRPV1- and CGRP-immunoreactive innervation in the dorsal horn was also observed. Our findings show that bortezomib-treatment selectively affects subsets of DRG neurons likely involved in the processing of nociceptive stimuli and that neurochemical changes may contribute to development and persistence of pain in bortezomib-induced PN. PMID:24877063

  11. Real-time ultrasound-guided comparison of adductor canal block and psoas compartment block combined with sciatic nerve block in laparoscopic knee surgeries

    PubMed Central

    Messeha, Medhat M.

    2016-01-01

    Background: Lumbar plexus block, combined with a sciatic nerve block, is an effective locoregional anesthetic technique for analgesia and anesthesia of the lower extremity. The aim of this study was to compare the clinical results outcome of the adductor canal block versus the psoas compartment block combined with sciatic nerve block using real time ultrasound guidance in patients undergoing elective laparoscopic knee surgeries. Patients and Methods: Ninety patients who were undergoing elective laparoscopic knee surgeries were randomly allocated to receive a sciatic nerve block in addition to lumbar plexus block using either an adductor canal block (ACB) or a posterior psoas compartment approach (PCB) using 25 ml of bupivacine 0.5% with adrenaline 1:400,000 injection over 2-3 minutes while observing the distribution of the local anesthetic in real time. Successful nerve block was defined as a complete loss of pinprick sensation in the region that is supplied by the three nerves along with adequate motor block, 30 minutes after injection. The degree of motor block was evaluated 30 minutes after the block procedure. The results of the present study showed that the real time ultrasound guidance of PCB is more effective than ACB approach. Although the sensory blockade of the femoral nerve achieved equally by both techniques, the LFC and OBT nerves were faster and more effectively blocked with PCB technique. Also PCB group showed significant complete sensory block without need for general anesthesia, significant decrease in the post-operative VAS and significant increase time of first analgesic requirement as compared to the ACB group. Result and Conclusion: The present study demonstrates that blockade of lumber plexus by psoas compartment block is more effective in complete sensory block without general anesthesia supplementation in addition to decrease post-operative analgesic requirement than adductor canal block. PMID:27212766

  12. Acute unilateral facial nerve palsy.

    PubMed

    Yeong, Siew Swan; Tassone, Peter

    2011-05-01

    Mrs PS, 78 years of age, presented with acute left-sided otalgia, ear swelling and subsequent unilateral facial paralysis (Figure 1). She denied any otorrhoea or hearing loss. Past medical history relevant to the presenting complaint included: * Bell palsy diagnosed 20 years ago with no residual effect * biopsy confirmed benign parotid lump (diagnosed 3 years previously). Histopathology revealed a pleomorphic adenoma. Mrs PS declined surgical intervention at the time * chicken pox as a child * normal fasting blood glucose 1 month previously and no known immune compromise. Examination revealed yellow crusts and small vesicles on the external acoustic meatus (Figure 2). A 10 mm well defined firm and nontender nodule was palpable at the ramus of the mandible.

  13. Hypoxia-Induced Upregulation of miR-132 Promotes Schwann Cell Migration After Sciatic Nerve Injury by Targeting PRKAG3.

    PubMed

    Yao, Chun; Shi, Xiangxiang; Zhang, Zhanhu; Zhou, Songlin; Qian, Tianmei; Wang, Yaxian; Ding, Fei; Gu, Xiaosong; Yu, Bin

    2016-10-01

    Following peripheral nerve injury, hypoxia is formed as a result of defects in blood supply at the injury site. Despite accumulating evidence on the effects of microRNAs (miRNAs) on phenotype modulation of Schwann cells (SCs) after peripheral nerve injury, the impact of hypoxia on SC behaviors through miRNAs during peripheral nerve regeneration has not been estimated. In this study, we confirmed our previous microarray data on the upregulation of miR-132 after sciatic nerve injury in rats and observed that overexpression of miR-132 significantly promoted cell migration of primary cultured SCs. Interestingly, hypoxia-increased expression of miR-132 also enhanced SC migration while inhibition of miR-132 suppressed hypoxia-induced increase in SC migration. miR-132 downregulated PRKAG3 through binding to its 3'-UTR, and PRKAG3 knockdown compromised the reducing effect of miR-132 inhibition on SC migration under normal or hypoxia condition. Moreover, in vivo injection of miR-132 agomir into rats with sciatic nerve transection accelerated SC migration from the proximal to distal stump. Overall, our results suggest that the hypoxia-induced upregulation of miR-132 could promote SC migration and facilitate peripheral nerve regeneration.

  14. Enhanced expression of the peripheral benzodiazepine receptor (PBR) and its endogenous ligand octadecaneuropeptide (ODN) in the regenerating adult rat sciatic nerve.

    PubMed

    Lacor, P; Benavides, J; Ferzaz, B

    1996-12-01

    In this study we have investigated the expression of the peripheral benzodiazepine receptor (PBR) and its endogenous ligand octadecaneuropeptide (ODN) in the sciatic nerve of the adult rat by immunohistochemistry. We have also determined the effect of nerve freezing lesion or chronic denervation on PBR and ODN expression. In the sciatic nerve of control rats PBR- and ODN-immunoreactivities (IR) were associated to Schwann cells. Ten days after nerve injury, PBR- and ODN-IR increased significantly in the distal stump. PBR-IR was associated to Schwann cells and macrophages, whereas ODN-IR was only detected in Schwann cells. Immunoreactivities returned to normal levels when axons were allowed to regenerate for 2 months after nerve freezing-injury. Under chronic denervation conditions, PBR- and ODN-IR remained elevated in the distal stump, at least for this period of time. These results suggest that PBR and ODN are regulated by signals from regenerating axons and that PBR and its endogenous ligand may play a role in peripheral nerve regeneration.

  15. Escalated regeneration in sciatic nerve crush injury by the combined therapy of human amniotic fluid mesenchymal stem cells and fermented soybean extracts, Natto

    PubMed Central

    Pan, Hung-Chuan; Yang, Dar-Yu; Ho, Shu-Peng; Sheu, Meei-Ling; Chen, Chung-Jung; Hwang, Shiaw-Min; Chang, Ming-Hong; Cheng, Fu-Chou

    2009-01-01

    Attenuation of inflammatory cell deposits and associated cytokines prevented the apoptosis of transplanted stem cells in a sciatic nerve crush injury model. Suppression of inflammatory cytokines by fermented soybean extracts (Natto) was also beneficial to nerve regeneration. In this study, the effect of Natto on transplanted human amniotic fluid mesenchymal stem cells (AFS) was evaluated. Peripheral nerve injury was induced in SD rats by crushing a sciatic nerve using a vessel clamp. Animals were categorized into four groups: Group I: no treatment; Group II: fed with Natto (16 mg/day for 7 consecutive days); Group III: AFS embedded in fibrin glue; Group IV: Combination of group II and III therapy. Transplanted AFS and Schwann cell apoptosis, inflammatory cell deposits and associated cytokines, motor function, and nerve regeneration were evaluated 7 or 28 days after injury. The deterioration of neurological function was attenuated by AFS, Natto, or the combined therapy. The combined therapy caused the most significantly beneficial effects. Administration of Natto suppressed the inflammatory responses and correlated with decreased AFS and Schwann cell apoptosis. The decreased AFS apoptosis was in line with neurological improvement such as expression of early regeneration marker of neurofilament and late markers of S-100 and decreased vacuole formation. Administration of either AFS, or Natto, or combined therapy augmented the nerve regeneration. In conclusion, administration of Natto may rescue the AFS and Schwann cells from apoptosis by suppressing the macrophage deposits, associated inflammatory cytokines, and fibrin deposits. PMID:19698158

  16. Sciatic nerve ligation causes impairment of mitochondria associated with changes in distribution, respiration, and cardiolipin composition in related spinal cord neurons in rats.

    PubMed

    Keilhoff, Gerburg; Becker, Axel; Kropf, Siegfried; Schild, Lorenz

    2016-10-01

    Sciatic nerve irritation is often associated with disturbed Ca(2+) homeostasis in related neurons of the spinal cord. Since mitochondria substantially contribute to Ca(2+) homeostasis and little information is available, we studied the effects of loose sciatic nerve ligation, a chronic constriction injury (CCI), on neuronal mitochondria of the L3-L6 regions. Three groups of rats (untreated, sham operated, and ligated) were explored. For the characterization of mitochondria, specimens of the L3-L6 spinal cord regions were evaluated with respect to intracellular localization using pyruvate dehydrogenase immunohistochemistry and Mitotracker Red, and the ATP producing machinery by LC-MS/MS technique for the analysis of cardiolipin and high-resolution respirometry for the measurement of oxygen consumption. Therefore, the phospholipid cardiolipin supports electron transfer within the respiratory chain as part of mitochondrial respiration and is of high impact on the physical properties of the mitochondrial membrane system. Histological analysis of spinal cord motor neurons revealed clustering of mitochondria in ipsilateral samples from ligated animals 14 days after the insult. This phenomenon was similarly evident in the respective contralateral side. The intensity of MT-Red staining was enhanced exclusively at the ipsilateral side, indicating increased mitochondrial activity. CCI of the sciatic nerve caused massive changes in the composition of cardiolipin reflecting mitochondrial impairment in the early phase followed by regeneration processes as late response. Sciatic nerve CCI caused decrease in the capacity of mitochondrial ATP production that recovered within 14 days after treatment. In conclusion, we provide evidence that clustering of mitochondria, already verified for the spinal cord sensory neurons after CCI, also occurs in the respective motor neurons. Further we have demonstrated transient impairment of the capacity of mitochondrial ATP production in tissue

  17. Protective effect of hesperetin in rat model of partial sciatic nerve ligation induced painful neuropathic pain: an evidence of anti-inflammatory and anti-oxidative activity.

    PubMed

    Aswar, Manoj; Kute, Prasad; Mahajan, Snehal; Mahajan, Umesh; Nerurkar, Geetanjali; Aswar, Urmila

    2014-09-01

    Behavioral, biochemical and gene expression changes were investigated in a rat model of partial sciatic nerve ligation (PSNL) after administration of hesperetin (20, 50mg/kg; p.o.), pregabalin (10mg/kg; p.o.) or vehicle (1 ml/kg, p.o.). Thirty-six animals were randomly divided into six groups. Left sciatic nerve was exposed and ligated, animals in the control and test groups were treated orally with respective drugs for fifteen days. Nociceptive threshold was assessed on 0 day and thereafter every three days. Three weeks later, sciatic nerve tissue homogenate was prepared and subjected for estimation of oxidative markers namely total protein, nitric oxide, lipid peroxidase, interleukins (IL-1β and IL-6) and TNF-α. Administration of hesperetin resulted in a dose dependent attenuation in PSNL-induced mechanical and thermal hyperalgesia, mechanical allodynia as well as down regulation of IL-1β, IL-6 and TNF-α, and biochemical markers. Consequently, it can be concluded that anti-hyperalgesic effect of hesperetin in rats after PSNL may be attributed to various oxidative markers as well as the pro-inflammatory mediators secreted at the injury site. Hesperetin appears to be a promising candidate for the development as a novel therapeutic for the patients suffering from the neuropathic pain.

  18. Dysregulated expression of death, stress and mitochondrion related genes in the sciatic nerve of presymptomatic SOD1G93A mouse model of Amyotrophic Lateral Sclerosis

    PubMed Central

    Alves, Chrystian J.; Maximino, Jessica R.; Chadi, Gerson

    2015-01-01

    Schwann cells are the main source of paracrine support to motor neurons. Oxidative stress and mitochondrial dysfunction have been correlated to motor neuron death in Amyotrophic Lateral Sclerosis (ALS). Despite the involvement of Schwann cells in early neuromuscular disruption in ALS, detailed molecular events of a dying-back triggering are unknown. Sciatic nerves of presymptomatic (60-day-old) SOD1G93A mice were submitted to a high-density oligonucleotide microarray analysis. DAVID demonstrated the deregulated genes related to death, stress and mitochondrion, which allowed the identification of Cell cycle, ErbB signaling, Tryptophan metabolism and Rig-I-like receptor signaling as the most representative KEGG pathways. The protein-protein interaction networks based upon deregulated genes have identified the top hubs (TRAF2, H2AFX, E2F1, FOXO3, MSH2, NGFR, TGFBR1) and bottlenecks (TRAF2, E2F1, CDKN1B, TWIST1, FOXO3). Schwann cells were enriched from the sciatic nerve of presymptomatic mice using flow cytometry cell sorting. qPCR showed the up regulated (Ngfr, Cdnkn1b, E2f1, Traf2 and Erbb3, H2afx, Cdkn1a, Hspa1, Prdx, Mapk10) and down-regulated (Foxo3, Mtor) genes in the enriched Schwann cells. In conclusion, molecular analyses in the presymptomatic sciatic nerve demonstrated the involvement of death, oxidative stress, and mitochondrial pathways in the Schwann cell non-autonomous mechanisms in the early stages of ALS. PMID:26339226

  19. Minimum effective local anesthetic volume for surgical anesthesia by subparaneural, ultrasound-guided popliteal sciatic nerve block: A prospective dose-finding study.

    PubMed

    Bang, Seung Uk; Kim, Dong Ju; Bae, Jin Ho; Chung, Kyudon; Kim, Yeesuk

    2016-08-01

    Because of its rapid onset time, recent years have seen an increase in the use of ultrasound (US)-guided popliteal sciatic nerve block (PSNB) via subparaneural injection for induction of surgical anesthesia. Moreover, in below-knee surgery, combined blocks, as opposed to sciatic nerve block alone, have become more common. These combined blocks often require a large volume of local anesthetic (LA), thus increasing the risk of local-anesthetic systemic toxicity (LAST). Thus, to decrease the risk of LAST, it is important to know the minimum effective volume (MEV) required for an adequate block. We, therefore, aimed to determine the MEV of ropivacaine 0.75% for induction of surgical anesthesia by the method of US-guided popliteal sciatic nerve block via subparaneural injection.Thirty patients underwent a US-guided PSNB with ropivacaine 0.75% at a 20-mL starting volume. Using a step-up/step-down method, we determined injection volumes for consecutive patients from the preceding patient's outcome. When an effective block was achieved within 40 minutes after injection, the next patient's volume was decreased by 2 mL. If the block failed, the next patient's volume was increased by 2 mL. The sensory and motor blockade was graded according to a 4-point scale. The block was considered a success if a combination of anesthesia and paresis (a score of 3 for both the sensory and motor nerves) was achieved within 40 minutes. The primary outcome measure was the MEV resulting in a successful subparaneural block of the sciatic nerve in 50% of patients (MEV50). Additionally, the data were processed with a probit regression analysis to determine the volume required to produce a complete sciatic nerve block in 90% of subjects (ED90).The MEV50 of 0.75% ropivacaine is 6.14 mL (95% confidence interval, 4.33-7.94 mL). The ED90 by probit analysis for a subparaneural injection was 8.9 mL (95% CI, 7.09-21.75 mL).The 6.14-mL MEV50 of ropivacaine 0.75% represents a 71% reduction

  20. [Neurons with Different Neurotransmitters in Embryonic Neocortical Allografts in the Rat Sciatic Nerve].

    PubMed

    Petrova, E S

    2016-01-01

    Different subsets of interneurons in the Wistar rat neocortex and in neocortical transplants developing in a damaged nerve were identified by the following immunohistochemical markers: glutamate decarboxylase (GAD 67) for GABAergic nerve cells, NO-synthase (NOS) for NO-ergic neurons, choline acetyltransferase (ChAT) for cholinergic cells, and tyrosine hydroxylase for catecholaminergic structures. Twenty-eight days after surgery, individual GAD 67-ir, NO-ir, ChAT-ir, and very rarely TH-ir cells were detected in the graft. It was shown that the number of GAD 67-ir neurons per unit area in the grafts was less than in the rat neocortex P20. PMID:27396173

  1. Essential Oil of Ocimum basilicum L. and (−)-Linalool Blocks the Excitability of Rat Sciatic Nerve

    PubMed Central

    Medeiros Venancio, Antonio; da Silva-Alves, Kerly Shamyra; de Carvalho Pimentel, Hugo; Macêdo Lima, Matheus; Fraga de Santana, Michele; Batista da Silva, Givanildo; Marchioro, Murilo

    2016-01-01

    The racemate linalool and its levogyrus enantiomer [(−)-LIN] are present in many essential oils and possess several pharmacological activities, such as antinociceptive and anti-inflammatory. In this work, the effects of essential oil obtained from the cultivation of the Ocimum basilicum L. (EOOb) derived from Germplasm Bank rich in (−)-LIN content in the excitability of peripheral nervous system were studied. We used rat sciatic nerve to investigate the EOOb and (−)-LIN effects on neuron excitability and the extracellular recording technique was used to register the compound action potential (CAP). EOOb and (−)-LIN blocked the CAP in a concentration-dependent way and these effects were reversible after washout. EOOb blocked positive amplitude of 1st and 2nd CAP components with IC50 of 0.38 ± 0.2 and 0.17 ± 0.0 mg/mL, respectively. For (−)-LIN, these values were 0.23 ± 0.0 and 0.13 ± 0.0 mg/mL. Both components reduced the conduction velocity of CAP and the 2nd component seems to be more affected than the 1st component. In conclusion EOOb and (−)-LIN inhibited the excitability of peripheral nervous system in a similar way and potency, revealing that the effects of EOOb on excitability are due to the presence of (−)-LIN in the essential oil. PMID:27446227

  2. Essential oil of Lippia alba and its main constituent citral block the excitability of rat sciatic nerves

    PubMed Central

    Sousa, D.G.; Sousa, S.D.G.; Silva, R.E.R.; Silva-Alves, K.S.; Ferreira-da-Silva, F.W.; Kerntopf, M.R.; Menezes, I.R.A.; Leal-Cardoso, J.H.; Barbosa, R.

    2015-01-01

    Lippia alba is empirically used for infusions, teas, macerates, and hydroalcoholic extracts because of its antispasmodic, analgesic, sedative, and anxiolytic effects. Citral is a mixture of trans-geranial and cis-neral and is the main constituent of L. alba essential oil and possesses analgesic, anxiolytic, anticonvulsant, and sedative effects. The present study evaluated the effects of the essential oil of L. alba (EOLa) and citral on compound action potentials (CAPs) in Wistar rat sciatic nerves. Both drugs inhibited CAP in a concentration-dependent manner. The calculated half-maximal inhibitory concentrations (IC50) of peak-to-peak amplitude were 53.2 µg/mL and 35.00 µg/mL (or 230 µM) for EOLa and citral, respectively. Peak-to-peak amplitude of the CAP was significantly reduced by 30 µg/mL EOLa and 10 µg/mL citral. EOLa and citral (at 60 and 30 µg/mL, values close to their respective IC50 for CAP blockade) significantly increased chronaxy and rheobase. The conduction velocity of the first and second CAP components was statistically reduced to ∼86% of control with 10 µg/mL EOLa and ∼90% of control with 3 µg/mL citral. This study showed that EOLa inhibited nerve excitability and this effect can be explained by the presence of citral in its composition. Both EOLa and citral showed inhibitory actions at lower concentrations compared with other essential oils and constituents with local anesthetic activity. In conclusion, these data demonstrate that EOLa and citral are promising agents in the development of new drugs with local anesthetic activity. PMID:26132093

  3. A New Preparation Method for Anisotropic Silk Fibroin Nerve Guidance Conduits and Its Evaluation In Vitro and in a Rat Sciatic Nerve Defect Model.

    PubMed

    Teuschl, Andreas Herbert; Schuh, Christina; Halbweis, Robert; Pajer, Krisztián; Márton, Gábor; Hopf, Rudolf; Mosia, Shorena; Rünzler, Dominik; Redl, Heinz; Nógrádi, Antal; Hausner, Thomas

    2015-09-01

    Over the past decade, silk fibroin (SF) has been emergently used in peripheral nerve tissue engineering. Current approaches aiming at producing SF-based nerve guidance conduits (SF-NGCs) used dissolved silk based on either aqueous solutions or organic solvents. In this study, we describe a novel procedure to produce SF-NGCs: A braided tubular structure of raw Bombyx mori silk is subsequently processed with the ternary solvent CaCl2/H2O/ethanol, formic acid, and methanol to improve its mechanical and topographical characteristics. Topographically, the combination of the treatments results in a fusion of the outer single silk fibers to a closed layer with a thickness ranging from about 40 to 75 μm. In contrast to the outer wall, the inner lumen (not treated with processing solvents) still represents the braided structure of single fibers. Mechanical stability, elasticity, and kink characteristics were evaluated with a custom-made test system. The modification procedure described here drastically improved the elastic properties of our tubular raw scaffold, favoring its use as a NGC. A cell migration assay with NIH/3T3-fibroblasts revealed the impermeability of the SF-NGC wall for possible invading and scar-forming cells. Moreover, the potential of the SF-NGC to serve as a substratum for Schwann cells has been demonstrated by cytotoxicity tests and live-dead stainings of Schwann cells grown on the inner surface of the SF-NGC. In vivo, the SF-NGC was tested in a rat sciatic nerve injury model. In short-term in vivo studies, it was proved that SF-NGCs are not triggering host inflammatory reactions. After 12 weeks, we could demonstrate morphological and functional reinnervation of the distal targets. Filled with collagen, a higher number of axons could be found in the distal to the graft (1678±303), compared with the empty SF-NGC (1274±146). The novel SF-NGC presented here shows promising results for the treatment of peripheral nerve injuries. The modification of

  4. A New Preparation Method for Anisotropic Silk Fibroin Nerve Guidance Conduits and Its Evaluation In Vitro and in a Rat Sciatic Nerve Defect Model

    PubMed Central

    Schuh, Christina; Halbweis, Robert; Pajer, Krisztián; Márton, Gábor; Hopf, Rudolf; Mosia, Shorena; Rünzler, Dominik; Redl, Heinz; Nógrádi, Antal; Hausner, Thomas

    2015-01-01

    Over the past decade, silk fibroin (SF) has been emergently used in peripheral nerve tissue engineering. Current approaches aiming at producing SF-based nerve guidance conduits (SF-NGCs) used dissolved silk based on either aqueous solutions or organic solvents. In this study, we describe a novel procedure to produce SF-NGCs: A braided tubular structure of raw Bombyx mori silk is subsequently processed with the ternary solvent CaCl2/H2O/ethanol, formic acid, and methanol to improve its mechanical and topographical characteristics. Topographically, the combination of the treatments results in a fusion of the outer single silk fibers to a closed layer with a thickness ranging from about 40 to 75 μm. In contrast to the outer wall, the inner lumen (not treated with processing solvents) still represents the braided structure of single fibers. Mechanical stability, elasticity, and kink characteristics were evaluated with a custom-made test system. The modification procedure described here drastically improved the elastic properties of our tubular raw scaffold, favoring its use as a NGC. A cell migration assay with NIH/3T3-fibroblasts revealed the impermeability of the SF-NGC wall for possible invading and scar-forming cells. Moreover, the potential of the SF-NGC to serve as a substratum for Schwann cells has been demonstrated by cytotoxicity tests and live-dead stainings of Schwann cells grown on the inner surface of the SF-NGC. In vivo, the SF-NGC was tested in a rat sciatic nerve injury model. In short-term in vivo studies, it was proved that SF-NGCs are not triggering host inflammatory reactions. After 12 weeks, we could demonstrate morphological and functional reinnervation of the distal targets. Filled with collagen, a higher number of axons could be found in the distal to the graft (1678±303), compared with the empty SF-NGC (1274±146). The novel SF-NGC presented here shows promising results for the treatment of peripheral nerve injuries. The modification of

  5. Repeatable and adjustable on-demand sciatic nerve block with phototriggerable liposomes.

    PubMed

    Rwei, Alina Y; Lee, Jung-Jae; Zhan, Changyou; Liu, Qian; Ok, Meryem T; Shankarappa, Sahadev A; Langer, Robert; Kohane, Daniel S

    2015-12-22

    Pain management would be greatly enhanced by a formulation that would provide local anesthesia at the time desired by patients and with the desired intensity and duration. To this end, we have developed near-infrared (NIR) light-triggered liposomes to provide on-demand adjustable local anesthesia. The liposomes contained tetrodotoxin (TTX), which has ultrapotent local anesthetic properties. They were made photo-labile by encapsulation of a NIR-triggerable photosensitizer; irradiation at 730 nm led to peroxidation of liposomal lipids, allowing drug release. In vitro, 5.6% of TTX was released upon NIR irradiation, which could be repeated a second time. The formulations were not cytotoxic in cell culture. In vivo, injection of liposomes containing TTX and the photosensitizer caused an initial nerve block lasting 13.5 ± 3.1 h. Additional periods of nerve block could be induced by irradiation at 730 nm. The timing, intensity, and duration of nerve blockade could be controlled by adjusting the timing, irradiance, and duration of irradiation. Tissue reaction to this formulation and the associated irradiation was benign. PMID:26644576

  6. Repeatable and adjustable on-demand sciatic nerve block with phototriggerable liposomes

    PubMed Central

    Rwei, Alina Y.; Lee, Jung-Jae; Zhan, Changyou; Liu, Qian; Ok, Meryem T.; Shankarappa, Sahadev A.; Langer, Robert; Kohane, Daniel S.

    2015-01-01

    Pain management would be greatly enhanced by a formulation that would provide local anesthesia at the time desired by patients and with the desired intensity and duration. To this end, we have developed near-infrared (NIR) light-triggered liposomes to provide on-demand adjustable local anesthesia. The liposomes contained tetrodotoxin (TTX), which has ultrapotent local anesthetic properties. They were made photo-labile by encapsulation of a NIR-triggerable photosensitizer; irradiation at 730 nm led to peroxidation of liposomal lipids, allowing drug release. In vitro, 5.6% of TTX was released upon NIR irradiation, which could be repeated a second time. The formulations were not cytotoxic in cell culture. In vivo, injection of liposomes containing TTX and the photosensitizer caused an initial nerve block lasting 13.5 ± 3.1 h. Additional periods of nerve block could be induced by irradiation at 730 nm. The timing, intensity, and duration of nerve blockade could be controlled by adjusting the timing, irradiance, and duration of irradiation. Tissue reaction to this formulation and the associated irradiation was benign. PMID:26644576

  7. Effect of Electroacupuncture on the Expression of Glycyl-tRNA Synthetase and Ultrastructure Changes in Atrophied Rat Peroneus Longus Muscle Induced by Sciatic Nerve Injection Injury

    PubMed Central

    Wang, Meng; Zhang, Xiao Ming; Yang, Sheng Bo

    2016-01-01

    Glycyl-tRNA synthetase (GlyRS) is one of the key enzymes involved in protein synthesis. Its mutations have been reported to cause Charcot-Marie-Tooth disease which demonstrates muscular atrophy in distal extremities, particularly manifested in peroneus muscles. In this situation, the dysfunctions of mitochondria and sarcoplasmic reticulum (SR) affect energy supply and excitation-contraction coupling of muscle fibers, therefore resulting in muscular atrophy. Although the treatment of muscular atrophy is a global urgent problem, it can be improved by electroacupuncture (EA) treatment. To investigate the mechanism underlying EA treatment improving muscular atrophy, we focused on the perspective of protein synthesis by establishing a penicillin injection-induced sciatic nerve injury model. In our model, injured rats without treatment showed decreased sciatic functional index (SFI), decreased peroneus longus muscle weight and muscle fiber cross-sectional area, aggregated mitochondria with vacuoles appearing, swollen SR, and downregulated mRNA and protein expression levels of GlyRS and myosin heavy chain IIb (MHC-IIb). The injured rats with EA treatment showed significant recovery. These results indicated that EA stimulation can alleviate peroneus longus muscular atrophy induced by iatrogenic sciatic nerve injury through promoting the recovery of GlyRS and muscle ultrastructure and increasing muscle protein synthesis. PMID:27274754

  8. Effect of Electroacupuncture on the Expression of Glycyl-tRNA Synthetase and Ultrastructure Changes in Atrophied Rat Peroneus Longus Muscle Induced by Sciatic Nerve Injection Injury.

    PubMed

    Wang, Meng; Zhang, Xiao Ming; Yang, Sheng Bo

    2016-01-01

    Glycyl-tRNA synthetase (GlyRS) is one of the key enzymes involved in protein synthesis. Its mutations have been reported to cause Charcot-Marie-Tooth disease which demonstrates muscular atrophy in distal extremities, particularly manifested in peroneus muscles. In this situation, the dysfunctions of mitochondria and sarcoplasmic reticulum (SR) affect energy supply and excitation-contraction coupling of muscle fibers, therefore resulting in muscular atrophy. Although the treatment of muscular atrophy is a global urgent problem, it can be improved by electroacupuncture (EA) treatment. To investigate the mechanism underlying EA treatment improving muscular atrophy, we focused on the perspective of protein synthesis by establishing a penicillin injection-induced sciatic nerve injury model. In our model, injured rats without treatment showed decreased sciatic functional index (SFI), decreased peroneus longus muscle weight and muscle fiber cross-sectional area, aggregated mitochondria with vacuoles appearing, swollen SR, and downregulated mRNA and protein expression levels of GlyRS and myosin heavy chain IIb (MHC-IIb). The injured rats with EA treatment showed significant recovery. These results indicated that EA stimulation can alleviate peroneus longus muscular atrophy induced by iatrogenic sciatic nerve injury through promoting the recovery of GlyRS and muscle ultrastructure and increasing muscle protein synthesis. PMID:27274754

  9. Changes in expression of two tetrodotoxin-resistant sodium channels and their currents in dorsal root ganglion neurons after sciatic nerve injury but not rhizotomy.

    PubMed

    Sleeper, A A; Cummins, T R; Dib-Hajj, S D; Hormuzdiar, W; Tyrrell, L; Waxman, S G; Black, J A

    2000-10-01

    Two TTX-resistant sodium channels, SNS and NaN, are preferentially expressed in c-type dorsal root ganglion (DRG) neurons and have been shown recently to have distinct electrophysiological signatures, SNS producing a slowly inactivating and NaN producing a persistent sodium current with a relatively hyperpolarized voltage-dependence. An attenuation of SNS and NaN transcripts has been demonstrated in small DRG neurons after transection of the sciatic nerve. However, it is not known whether changes in the currents associated with SNS and NaN or in the expression of SNS and NaN channel protein occur after axotomy of the peripheral projections of DRG neurons or whether similar changes occur after transection of the central (dorsal root) projections of DRG neurons. Peripheral and central projections of L4/5 DRG neurons in adult rats were axotomized by transection of the sciatic nerve and the L4 and L5 dorsal roots, respectively. DRG neurons were examined using immunocytochemical and patch-clamp methods 9-12 d after sciatic nerve or dorsal root lesion. Levels of SNS and NaN protein in the two types of injuries were paralleled by their respective TTX-resistant currents. There was a significant decrease in SNS and NaN signal intensity in small DRG neurons after peripheral, but not central, axotomy compared with control neurons. Likewise, there was a significant reduction in slowly inactivating and persistent TTX-resistant currents in these neurons after peripheral, but not central, axotomy compared with control neurons. These results indicate that peripheral, but not central, axotomy results in a reduction in expression of functional SNS and NaN channels in c-type DRG neurons and suggest a basis for the altered electrical properties that are observed after peripheral nerve injury. PMID:11007885

  10. Regulation of the expression of peripheral benzodiazepine receptors and their endogenous ligands during rat sciatic nerve degeneration and regeneration: a role for PBR in neurosteroidogenesis.

    PubMed

    Lacor, P; Gandolfo, P; Tonon, M C; Brault, E; Dalibert, I; Schumacher, M; Benavides, J; Ferzaz, B

    1999-01-01

    Peripheral benzodiazepine receptors (PBR) and their endogenous ligands, the diazepam-binding inhibitor derived-peptides, are present in Schwann cells in the peripheral nervous system. The aim of this study was to determine the influence of reversible (freeze-injury) and permanent (transection and ligature) nerve lesion on PBR density and on the levels of their endogenous ligands, by autoradiography (using [3H]PK11195) and radioimmunoassay (using antisera directed against the octadecaneuropeptide (ODN), a diazepam-binding inhibitor fragment). The potential role of PBR on peripheral nerve steroidogenesis, was studied by investigating the effect of specific PBR agonists and antagonists on pregnenolone levels in the sciatic nerve. Sixteen to 30 days after nerve lesion, PBR density and ODN-LI level were highly increased. Their expression returned to normal level when regeneration was completed 60 days after freeze-injury, but remained elevated when regeneration did not occur in transected distal stumps. Reverse-phase HPLC analysis of ODN-LI showed that in control nerve extracts, the major immunoreactive peak co-elutes with triakontatetraneuropeptide (TTN). After freeze-injury, intermediate molecular forms eluting between ODN and TTN were predominant and remained elevated at day 60. The greater accumulation of intermediate forms when regeneration is allowed to occur may indicate a particular role of these forms in axonal elongation and myelination. Ro5-4864, a high affinity PBR agonist increased pregnenolone concentration in the sciatic nerve. This effect was antagonised by PK11195, a high affinity PBR antagonist, which had no effect on pregnenolone basal level, indicating a specific action of PBR in neurosteroid production. These results suggest a role for PBR and their endogenous ligands in peripheral nerve regeneration. A trophic effect could be exerted via stimulation of steroid synthesis.

  11. Assessing the axonal translocation of CeO2 and SiO2 nanoparticles in the sciatic nerve fibers of the frog: an ex vivo electrophysiological study

    PubMed Central

    Kastrinaki, Georgia; Samsouris, Christos; Kosmidis, Efstratios K; Papaioannou, Eleni; Konstandopoulos, Athanasios G; Theophilidis, George

    2015-01-01

    The axonal translocation of two commonly used nanoparticles in medicine, namely CeO2 and SiO2, is investigated. The study was conducted on frog sciatic nerve fibers in an ex vivo preparation. Nanoparticles were applied at the proximal end of the excised nerve. A nerve stimulation protocol was followed for over 35 hours. Nerve vitality curve comparison between control and exposed nerves showed that CeO2 has no neurotoxic effect at the concentrations tested. After exposure, specimens were fixed and then screen scanned every 1 mm along their length for nanoparticle presence by means of Fourier transform infrared microscopy. We demonstrated that both nanoparticles translocate within the nerve by formation of narrow bands in the Fourier transform infrared spectrum. For the CeO2, we also demonstrated that the translocation depends on both axonal integrity and electrical activity. The speed of translocation for the two species was estimated in the range of 0.45–0.58 mm/h, close to slow axonal transportation rate. Transmission electron microscopy provided direct evidence for the presence of SiO2 in the treated nerves. PMID:26648718

  12. Chitosan/silk fibroin-based, Schwann cell-derived extracellular matrix-modified scaffolds for bridging rat sciatic nerve gaps.

    PubMed

    Gu, Yun; Zhu, Jianbin; Xue, Chengbin; Li, Zhenmeiyu; Ding, Fei; Yang, Yumin; Gu, Xiaosong

    2014-02-01

    Extracellular matrix (ECM) plays a prominent role in establishing and maintaining an ideal microenvironment for tissue regeneration, and ECM scaffolds are used as a feasible alternative to cellular and molecular therapy in the fields of tissue engineering. Because of their advantages over tissue-derived ECM scaffolds, cultured cell-derived ECM scaffolds are beginning to attract attention, but they have been scarcely studied for peripheral nerve repair. Here we aimed to develop a tissue engineered nerve scaffold by reconstituting nerve cell-derived ECM with natural biomaterials. A protocol was adopted to prepare and characterize the cultured Schwann cell (SC)-derived ECM. A chitosan conduit and silk fibroin (SF) fibers were prepared, cultured with SCs for ECM deposition, and subjected to decellularization, followed by assembly into a chitosan/SF-based, SC-derived ECM-modified scaffold, which was used to bridge a 10 mm rat sciatic nerve gap. The results from morphological analysis as well as electrophysiological examination indicated that regenerative outcomes achieved by our developed scaffold were similar to those by an acellular nerve graft (namely a nerve tissue-derived ECM scaffold), but superior to those by a plain chitosan/SF scaffold. Moreover, blood and histopathological parameters confirmed the safety of scaffold modification by SC-derived ECM. Therefore, a hybrid scaffold based on joint use of acellular and classical biomaterials represents a promising approach to nerve tissue engineering.

  13. ProNGF derived from rat sciatic nerves downregulates neurite elongation and axon specification in PC12 cells

    PubMed Central

    Trigos, Anna Sofía; Longart, Marines; García, Lisbeth; Castillo, Cecilia; Forsyth, Patricia; Medina, Rafael

    2015-01-01

    Several reports have shown that a sciatic nerve conditioned media (CM) causes neuronal-like differentiation in PC12 cells. This differentiation is featured by neurite outgrowth, which are exclusively dendrites, without axon or sodium current induction. In previous studies, our group reported that the CM supplemented with a generic inhibitor for tyrosine kinase receptors (k252a) enhanced the CM-induced morphological differentiation upregulating neurite outgrowth, axonal formation and sodium current elicitation. Sodium currents were also induced by depletion of endogenous precursor of nerve growth factorr (proNGF) from the CM (pNGFd-CM). Given that sodium currents, neurite outgrowth and axon specification are important features of neuronal differentiation, in the current manuscript, first we investigated if proNGF was hindering the full PC12 cell neuronal-like differentiation. Second, we studied the effects of exogenous wild type (pNGFwt) and mutated (pNGFmut) proNGF isoforms over sodium currents and whether or not their addition to the pNGFd-CM would prevent sodium current elicitation. Third, we investigated if proNGF was exerting its negative regulation through the sortilin receptor, and for this, the proNGF action was blocked with neurotensin (NT), a factor known to compete with proNGF for sortilin. Thereby, here we show that pNGFd-CM enhanced cell differentiation, cell proportion with long neurites, total neurite length, induced axonal formation and sodium current elicitation. Interestingly, treatment of PC12 cells with wild type or mutated proNGF isoforms elicited sodium currents. Supplementing pNGFd-CM with pNGFmut reduced 35% the sodium currents. On the other hand, pNGFd-CM+pNGFwt induced larger sodium currents than pNGFd-CM. Finally, treatments with CM supplemented with NT showed that sortilin was mediating proNGF negative regulation, since its blocking induced similar effects than the pNGFd-CM treatment. Altogether, our results suggest that proNGF within the

  14. Localization and expression of ciliary neurotrophic factor (CNTF) in postmortem sciatic nerve from patients with motor neuron disease and diabetic neuropathy

    SciTech Connect

    Lee, D.A.; Gross, L.; Wittrock, D.A.; Windebank, A.J.

    1996-08-01

    Ciliary neurotrophic factor (CNTF) is thought to play an important role in the maintenance of the mature motor system. The factor is found most abundantly in myelinating Schwann cells in the adult sciatic nerve. Lack of neuronal growth factors has been proposed as one possible etiology of amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA). Growth factor replacement therapies are currently being evaluated as a treatment for motor neuron disease. In this report we determined whether the expression of CNTF in sciatic nerve differed in patients with motor neuron disease compared to controls or patients with another form of axonopathy. We identified 8 patients (7 with ALS and 1 with SMA) with motor neuron disease and 6 patients with diabetic motor neuropathy who had autopsy material available. Immunoperoxidase staining showed reduced CNTF expression in nerves of patients with motor neuron disease but not in patients with diabetic motor neuropathy. Decreased CNTF appears be associated with primary motor neuron disease rather than a generalized process of axon loss. This result supports suggestions that CNTF deficiency may be an important factor in the development of motor neuron disease. 20 refs., 4 figs., 1 tab.

  15. Changes in nerve function and nerve fibre structure induced by acute, graded compression.

    PubMed Central

    Rydevik, B; Nordborg, C

    1980-01-01

    Rabbit tibial nerves were subjected to direct, acute graded compression by means of an inflatable compression chamber. The acute and long term effects of 50, 200 and 400 mmHg applied for two hours on nerve function and nerve fibre structure were investigated. A pressure of 50 mmHg applied for two hours induced only minimal or no acute deterioration of maximal conduction velocity and nerve fibre structure. Conduction velocity was gradually reduced during compression at 200-400 mmHg pressure for two hours and in those cases the recovery of nerve conduction after pressure release was incomplete. Ultrastructural analysis revealed pronounced, early nerve fibre damage in these nerves. Three weeks after compression, nerves compressed at 50 mmHg for two hours had normal afferent and motor conduction velocity, although there were morphological signs of slight nerve fibre damage. Nerves compressed at 200 mmHg for two hours exhibited reduction of conduction velocity only at the level of compression, in contrast to the nerves compressed at 400 mmHg for two hours in which conduction velocity was reduced both at the level of compression and distal to the compressed segment. Morphologically, the nerves compressed at 200-400 mmHg for two hours showed varying degrees of demyelination and axonal degeneration three weeks after compression. Images PMID:7217952

  16. Nuclear factor erythroid 2-related factor 2 antibody attenuates thermal hyperalgesia in the dorsal root ganglion: Neurochemical changes and behavioral studies after sciatic nerve-pinch injury.

    PubMed

    Xiang, Qiong; Yu, Chao; Zhu, Yao-Feng; Li, Chun-Yan; Tian, Rong-Bo; Li, Xian-Hui

    2016-08-01

    Oxidative stress is generated in several peripheral nerve injury models.Nuclear factor erythroid 2-related factor 2 (Nrf2) is activated to have a role in antioxidant effect. After nerve injury, the severely painful behavior is also performed. However, little has been explored regarding the function of Nrf2 in this painful process. Therefore, in this study, we compared the effects of Nrf2 antibody administration following sciatic nerve-pinch injury on painful behavior induced in young mice and neurochemical changes in dorsal root ganglion neurons. After pinch nerve injury, we found that the magnitude of the thermal allodynia was significantly decreased after application of Nrf2 antibody (5ul, 1mg/ml) in such injured animals and phosphorylated ERK(p-ERK) as well as the apoptotic protein (i.e., Bcl-6) in DRG neurons were also down-regulated in the anti-Nrf2-treated injured groups compared to the saline-treated groups. Taken collectively, these data suggested that the Nrf2 antibody reduced thermal hyperalgesia via ERK pathway and the down regulation of Bcl-6 protein from the apoptosis pathway might be protecting against the protein deletions caused by anti-Nrf2 effect and suggested the new therapeutic strategy with Nrf2 inhibitor following nerve injury. PMID:27316447

  17. Linear Ordered Collagen Scaffolds Loaded with Collagen-Binding Basic Fibroblast Growth Factor Facilitate Recovery of Sciatic Nerve Injury in Rats

    PubMed Central

    Ma, Fukai; Xiao, Zhifeng; Chen, Bing; Hou, Xianglin

    2014-01-01

    Natural biological functional scaffolds, consisting of biological materials filled with promoting elements, provide a promising strategy for the regeneration of peripheral nerve defects. Collagen conduits have been used widely due to their excellent biological properties. Linear ordered collagen scaffold (LOCS) fibers are good lumen fillers that can guide nerve regeneration in an ordered direction. In addition, basic fibroblast growth factor (bFGF) is important in the recovery of nerve injury. However, the traditional method for delivering bFGF to the lesion site has no long-term effect because of its short half-life and rapid diffusion. Therefore, we fused a specific collagen-binding domain (CBD) peptide to the N-terminal of native basic fibroblast growth factor (NAT-bFGF) to retain bFGF on the collagen scaffolds. In this study, a natural biological functional scaffold was constructed using collagen tubes filled with collagen-binding bFGF (CBD-bFGF)-loaded LOCS to promote regeneration in a 5-mm rat sciatic nerve transection model. Functional evaluation, histological investigation, and morphometric analysis indicated that the natural biological functional scaffold retained more bFGF at the injury site, guided axon growth, and promoted nerve regeneration as well as functional restoration. PMID:24188561

  18. Assessment of functional recovery of sciatic nerve in rats submitted to low-level laser therapy with different fluences. An experimental study: laser in functional recovery in rats.

    PubMed

    Marcolino, Alexandre Marcio; Barbosa, Rafael Inácio; das Neves, Lais Mara Siqueira; Mazzer, Nilton; de Jesus Guirro, Rinaldo Roberto; de Cássia Registro Fonseca, Marisa

    2013-12-01

    Peripheral nerve lesions caused sensory and motor deficits along the distribution of the injured nerve. Numerous researches have been carried out to enhance and/or accelerate the recovery of such lesions. The objective of this study was to assess the functional recovery of sciatic nerve in rats subjected to different fluences of low-level laser therapy (LLLT). Thirty-six animals were randomly divided into four groups: one consisting of sham rats and three others irradiated with progressive fluencies of 10 J/cm(2), 40 J/cm(2) and 80 J/cm(2) of laser AsGaAl (830 nm) for 21 consecutive days. They were evaluated by the Sciatic Functional Index (SFI) method. The crush injury was performed by using a portable device with dead weight of 5,000 g whose load was applied for 10 min. A digital camera was used to record the footprints left on the acrylic track, before surgery and after, on the 7th, 14th, and 21st days. The results also showed that on the 7th day, there was a difference between the groups irradiated with 40 J/cm(2), when compared with the sham group (p < 0.05). On the 14th day the groups irradiated with 40 J/cm(2) and 80 J/cm(2) also presented better results when compared with sham, however, on the 21st day, no inter-group difference was found (p > 0.05). It was possible to observe that the LLLT at fluency of 40 J/cm(2) and 80 J/cm(2) had a positive influence on the acceleration of the functional nerve recovery. PMID:24426674

  19. Assessment of functional recovery of sciatic nerve in rats submitted to low-level laser therapy with different fluences. An experimental study: laser in functional recovery in rats.

    PubMed

    Marcolino, Alexandre Marcio; Barbosa, Rafael Inácio; das Neves, Lais Mara Siqueira; Mazzer, Nilton; de Jesus Guirro, Rinaldo Roberto; de Cássia Registro Fonseca, Marisa

    2013-12-01

    Peripheral nerve lesions caused sensory and motor deficits along the distribution of the injured nerve. Numerous researches have been carried out to enhance and/or accelerate the recovery of such lesions. The objective of this study was to assess the functional recovery of sciatic nerve in rats subjected to different fluences of low-level laser therapy (LLLT). Thirty-six animals were randomly divided into four groups: one consisting of sham rats and three others irradiated with progressive fluencies of 10 J/cm(2), 40 J/cm(2) and 80 J/cm(2) of laser AsGaAl (830 nm) for 21 consecutive days. They were evaluated by the Sciatic Functional Index (SFI) method. The crush injury was performed by using a portable device with dead weight of 5,000 g whose load was applied for 10 min. A digital camera was used to record the footprints left on the acrylic track, before surgery and after, on the 7th, 14th, and 21st days. The results also showed that on the 7th day, there was a difference between the groups irradiated with 40 J/cm(2), when compared with the sham group (p < 0.05). On the 14th day the groups irradiated with 40 J/cm(2) and 80 J/cm(2) also presented better results when compared with sham, however, on the 21st day, no inter-group difference was found (p > 0.05). It was possible to observe that the LLLT at fluency of 40 J/cm(2) and 80 J/cm(2) had a positive influence on the acceleration of the functional nerve recovery.

  20. Fasinumab (REGN475), an antinerve growth factor monoclonal antibody, for the treatment of acute sciatic pain: results of a proof-of-concept study

    PubMed Central

    Tiseo, Paul J; Ren, Haobo; Mellis, Scott

    2014-01-01

    Objective To evaluate the efficacy and safety of subcutaneously administered fasinumab (REGN475), a nerve growth factor-neutralizing antibody, in patients with acute sciatic pain receiving standard of care therapy. Methods This was a double-blind, parallel-group, proof-of-concept study. Patients with unilateral, moderate-to-severe sciatic pain of 2–16 weeks’ duration were randomized to a subcutaneous dose of placebo (n=51), fasinumab 0.1 mg/kg (n=53), or 0.3 mg/kg (n=53); follow-up was 12 weeks. Pain was assessed in a daily diary using a numerical rating scale (NRS) (0= no pain, 10= worst pain) for average and worst leg and back pain. The primary efficacy end point was the area under the curve of NRS scores for average leg pain from baseline to week 4. Key secondary end points included changes in average and worst leg and back pain from baseline to the end of week 4 and to each weekly study visit. Patient functioning (Oswestry Disability Index) and concomitant analgesic use were also assessed. Safety and tolerability were evaluated by treatment-emergent adverse events (TEAEs). Results Demographic and clinical characteristics were similar among the treatment groups; 141 (88.7%) patients completed the study. For the primary end point, mean ± standard deviation area under the curve values from baseline to week 4 were not significantly different between placebo (96.8±6.0) and fasinumab 0.1 mg/kg (112.7±58.3; P=0.0610) or fasinumab 0.3 mg/kg (112.4±55.8; P=0.0923). All secondary efficacy end points of changes in pain and function demonstrated responses that were similar between placebo and fasinumab groups. Incidence of TEAEs was 45.1%, 50.9%, and 64.8% in the placebo, fasinumab 0.1mg/kg, and fasinumab 0.3 mg/kg groups, respectively. The most commonly reported TEAEs included paresthesia, arthralgia, pain in extremity, and headache. Conclusion Administration of fasinumab provided no significant clinical benefit compared with placebo for the pain or functional

  1. Effect of pH of bupivacaine on duration of repeated sciatic nerve blocks in the albino rat. Local Anesthetics for Neuralgia Study Group.

    PubMed

    Baker, C E; Berry, R L; Elston, R C

    1991-06-01

    Tachyphylaxis has been ascribed to tissue acidification after repeated injections of acidic local anesthetic solutions. We studied the effect of pH on the duration of action of bupivacaine to determine the validity of this proposed mechanism of tachyphylaxis by injecting bupivacaine solutions adjusted to pH 4.2 or 6.8 into a surgically implanted system created to permit in vivo irrigation of rat sciatic nerves with local anesthetic. Tachyphylaxis developed at both pH values. The results fail to support the acidification hypothesis as there was no statistically significant effect of a 400-fold difference in hydrogen ion concentration on the development of tachyphylaxis or the duration of motor dysfunction.

  2. Difference in intraosseous blood vessel volume and number in osteoporotic model mice induced by spinal cord injury and sciatic nerve resection.

    PubMed

    Ding, Wen-Ge; Yan, Wei-hong; Wei, Zhao-Xiang; Liu, Jin-Bo

    2012-07-01

    In the present study, we examined intraosseous blood vessel parameters of the tibial metaphysis in mice using microcomputed tomography (µCT) to investigate the relationship between post-nerve-injury osteoporosis and local intraosseous blood vessel volume and number. Mice were randomly divided into groups receiving spinal cord injury (SCI), sciatic nerve resection group (NX), or intact controls (30 mice/group). Four weeks after surgery, mice were perfused with silicone and the distribution of intraosseous blood vessels analyzed by μCT. The bone density, μCT microstructure, biomechanical properties, and the immunohistochemical and biochemical indicators of angiogenesis were also measured. The SCI group showed significantly reduced tibial metaphysis bone density, μCT bone microstructure, tibial biomechanical properties, indicators of angiogenesis, and intraosseous blood vessel parameters compared to the NX group. Furthermore, the spinal cord-injured mice exhibited significantly decreased intraosseous blood vessel volume and number during the development of osteoporosis. In conclusion, these data suggest that decreased intraosseous blood vessel volume and number may play an important role in the development of post-nerve-injury osteoporosis.

  3. Time Course of Immediate Early Gene Protein Expression in the Spinal Cord following Conditioning Stimulation of the Sciatic Nerve in Rats

    PubMed Central

    Bojovic, Ognjen; Panja, Debabrata; Bittins, Margarethe; Bramham, Clive R.; Tjølsen, Arne

    2015-01-01

    Long-term potentiation induced by conditioning electrical stimulation of afferent fibers is a widely studied form of synaptic plasticity in the brain and the spinal cord. In the spinal cord dorsal horn, long-term potentiation is induced by a series of high-frequency trains applied to primary afferent fibers. Conditioning stimulation (CS) of sciatic nerve primary afferent fibers also induces expression of immediate early gene proteins in the lumbar spinal cord. However, the time course of immediate early gene expression and the rostral-caudal distribution of expression in the spinal cord have not been systematically studied. Here, we examined the effects of sciatic nerve conditioning stimulation (10 stimulus trains, 0.5 ms stimuli, 7.2 mA, 100 Hz, train duration 2 s, 8 s intervals between trains) on cellular expression of immediate early genes, Arc, c-Fos and Zif268, in anesthetized rats. Immunohistochemical analysis was performed on sagittal sections obtained from Th13- L5 segments of the spinal cord at 1, 2, 3, 6 and 12 h post-CS. Strikingly, all immediate early genes exhibited a monophasic increase in expression with peak increases detected in dorsal horn neurons at 2 hours post-CS. Regional analysis showed peak increases at the location between the L3 and L4 spinal segments. Both Arc, c-Fos and Zif268 remained significantly elevated at 2 hours, followed by a sharp decrease in immediate early gene expression between 2 and 3 hours post-CS. Colocalization analysis performed at 2 hours post-CS showed that all c-Fos and Zif268 neurons were positive for Arc, while 30% and 43% of Arc positive neurons were positive for c-Fos and Zif268, respectively. The present study identifies the spinal cord level and time course of immediate early gene (IEGP) expression of relevance for analysis of IEGPs function in neuronal plasticity and nociception. PMID:25860146

  4. Spatio-temporal characteristics of cerebral blood volume changes in different microvascular compartments evoked by sciatic nerve stimulation in rat somatosensory cortex

    NASA Astrophysics Data System (ADS)

    Li, Pengcheng; Luo, Qingming; Luo, Weihua; Chen, Shangbin; Chen, Haiying; Zeng, Shaoqun

    2003-10-01

    The spatio-temporal characteristics of changes in cerebral blood volume associated with neuronal activity were investigated in the hindlimb somatosensory cortex of α-chloralose/urethan anesthetized rats (n=10) with optical imaging at 570nm through a thinned skull. Activation of cortex was carried out by electrical stimulation of the contralateral sciatic nerve with 5Hz, 0.3V pulses (0.5ms) for duration of 2s. The stimulation evoked a monophasic optical reflectance decrease at cortical parenchyma and arteries sites rapidly after the onset of stimulation, whereas no similar response was observed at vein compartments. The optical signal changes reached 10% of the peak response 0.70+/-0.32s after stimulation onset and no significant time lag in this 10% start latency time was observed between the response at cortical parenchyma and arteries compartments. The evoked optical reflectance decrease reached the peak (0.25%+/-0.047%)2.66+/-0.61s after the stimulus onset at parenchyma site, 0.40+/-0.20s earlier (P<0.05) than that at arteries site (0.50%+/-0.068% 3.06+/-0.70s). Variable location within the cortical parenchyma and arteries compartment themselves didn"t affect the temporal characteristics of the evoked signal significantly. These results suggest that the sciatic nerve stimulation evokes a local blood volume increase at both capillaries (cortical parenchyma) and arterioles rapidly after the stimulus onset but the evoked blood volume increase in capillaries could not be entirely accounted for by the dilation of arterioles.

  5. Effects of 660- and 980-nm low-level laser therapy on neuropathic pain relief following chronic constriction injury in rat sciatic nerve.

    PubMed

    Masoumipoor, M; Jameie, S B; Janzadeh, A; Nasirinezhad, F; Soleimani, M; Kerdary, M

    2014-09-01

    Neuropathic pain (NP) is one of the most suffered conditions in medical disciplines. The role of reactive oxygen species (ROS) and oxidative stress in the induction of NP was studied by many researchers. Neuropathies lead to medical, social, and economic isolation of the patient, so various therapies were used to treat or reduce it. During the recent years, low-level laser therapy (LLLT) has been used in certain areas of medicine and rehabilitation. Chronic constriction injury (CCI) is a well-known model for neuropathic pain studies. In order to find the effects of different wavelengths of LLLT on the injured sciatic nerve, the present research was done. Thirty Wistar adult male rats (230-320 g) were used in this study. The animals were randomly divided into three groups (n = 10). To induce neuropathic pain for the sciatic nerve, the CCI technique was used. Low-level laser of 660 and 980 nm was used for two consecutive weeks. Thermal and mechanical hyperalgesia was done before and after surgery on days 7 and 14, respectively. Paw withdrawal thresholds were also evaluated. CCI decreased the pain threshold, whereas both wavelengths of LLLT for 2 weeks increased mechanical and thermal threshold significantly. A comparison of the mechanical and thermal threshold showed a significant difference between the therapeutic effects of the two groups that received LLLT. Based on our findings, the laser with a 660-nm wavelength had better therapeutic effects than the laser with a 980-nm wavelength, so the former one may be used for clinical application in neuropathic cases; however, it needs more future studies.

  6. Acute anoxic changes in peripheral nerve: anatomic and physiologic correlations

    PubMed Central

    Punsoni, Michael; Drexler, Steven; Palaia, Thomas; Stevenson, Matthew; Stecker, Mark M

    2015-01-01

    Introduction The response of the peripheral nerve to anoxia is modulated by many factors including glucose and temperature. The purposes of this article are to demonstrate the effects of these factors on the pathological changes induced by anoxia and to compare the electrophysiologic changes and pathological changes in the same nerves. Methods Sciatic nerves were harvested from rats and placed in a perfusion apparatus where neurophysiologic responses could be recorded continuously during a 16 h experiment. After the experiment, light microscopy and electron microscopy were performed. Results Light microscopic images showed mild changes from anoxia at normoglycemia. Hypoglycemic anoxia produced massive axonal swelling while hyperglycemic anoxia produced apparent changes in the myelin. Anoxic changes were not uniform in all axons. Electron microscopy showed only minor disruptions of the cytoskeleton with anoxia during normoglycemia. At the extremes of glucose concentration especially with hyperglycemia, there was a more severe disruption of intermediate filaments and loss of axonal structure with anoxia. Hypothermia protected axons from the effect of anoxia and produced peak axonal swelling in the 17–30°C range. Conclusions The combination of hyperglycemia or hypoglycemia and anoxia produces extremely severe axonal disruption. Changes in axonal diameter are complex and are influenced by many factors. PMID:26221572

  7. Combination of Local Transplantation of In Vitro Bone-marrow Stromal Cells and Pulsed Electromagnetic Fields Accelerate Functional Recovery of Transected Sciatic Nerve Regeneration: A Novel Approach in Transected Nerve Repair.

    PubMed

    Mohammadi, Rahim; Mahmoodzadeh, Sirvan

    2015-01-01

    Effect of combination of undifferentiated bone marrow stromal cells (BMSCs) and pulsed electromagnetic fields (PEMF) on transected sciatic nerve regeneration was assessed in rats. A 10 mm nerve segment was excised and a vein graft was used to bridge the gap. Twenty microliter undifferentiated BMSCs (2× 107 cells /mL) were administered into the graft inBMSC group with no exposure to PEMF. In BMSC/PEMF group the whole body was exposed to PEMF (0.3 mT, 2Hz) for 4h/day within 1-5 days. In PEMF group the transected nerve was bridged and phosphate buffered saline was administered into the graft. In authograft group (AUTO), the transected nervesegments were reimplanted reversely and the whole body was exposed to PEMF. The regenerated nerve fibers were studied within 12 weeks after surgery. Behavioral, functional, electrophysiological, biomechanical, gastrocnemius muscle mass findings, morphometric indices and immuonohistochemical reactions confirmed faster recovery of regenerated axons in BMSC/PEMF group compared to those in the other groups (P<0.05). The use of undifferentiated BMSCs with whole body exposure to PEMF improved functional recovery. Combination of local transplantation of in vitro bone-marrow stromal cells and pulsed electromagnetic fields could be considered as an effective, safe and tolerable treatment for peripheral nerve repair in clinical practice.

  8. A role for apolipoprotein E, apolipoprotein A-I, and low density lipoprotein receptors in cholesterol transport during regeneration and remyelination of the rat sciatic nerve.

    PubMed Central

    Boyles, J K; Zoellner, C D; Anderson, L J; Kosik, L M; Pitas, R E; Weisgraber, K H; Hui, D Y; Mahley, R W; Gebicke-Haerter, P J; Ignatius, M J

    1989-01-01

    Recent work has demonstrated that apo E secretion and accumulation increase in the regenerating peripheral nerve. The fact that apoE, in conjunction with apoA-I and LDL receptors, participates in a well-established lipid transfer system raised the possibility that apoE is also involved in lipid transport in the injured nerve. In the present study of the crushed rat sciatic nerve, a combination of techniques was used to trace the cellular associations of apoE, apoA-I, and the LDL receptor during nerve repair and to determine the distribution of lipid at each stage. After a crush injury, as axons died and Schwann cells reabsorbed myelin, resident and monocyte-derived macrophages produced large quantities of apoE distal to the injury site. As axons regenerated in the first week, their tips contained a high concentration of LDL receptors. After axon regeneration, apoE and apoA-I began to accumulate distal to the injury site and macrophages became increasingly cholesterol-loaded. As remyelination began in the second and third weeks after injury, Schwann cells exhausted their cholesterol stores, then displayed increased LDL receptors. Depletion of macrophage cholesterol stores followed over the next several weeks. During this stage of regeneration, apoE and apoA-I were present in the extracellular matrix as components of cholesterol-rich lipoproteins. Our results demonstrate that the regenerating peripheral nerve possesses the components of a cholesterol transfer mechanism, and the sequence of events suggests that this mechanism supplies the cholesterol required for rapid membrane biogenesis during axon regeneration and remyelination. Images PMID:2493483

  9. Cold bupivacaine versus magnesium sulfate added to room temperature bupivacaine in sonar-guided femoral and sciatic nerve block in arthroscopic anterior cruciate ligament reconstruction surgery

    PubMed Central

    Alzeftawy, Ashraf Elsayed; El-Daba, Ahmad Ali

    2016-01-01

    Background: Cooling of local anesthetic potentiates its action and increases its duration. Magnesium sulfate (MgSo4) added to local anesthetic prolongs the duration of anesthesia and postoperative analgesia with minimal side effects. Aim: The aim of this prospective, randomized, double-blind study was to compare the effect of cold to 4°C bupivacaine 0.5% and Mg added to normal temperature (20–25°C) bupivacaine 0.5% during sonar-guided combined femoral and sciatic nerve blocks on the onset of sensory and motor block, intraoperative anesthesia, duration of sensory and motor block, and postoperative analgesia in arthroscopic anterior cruciate ligament (ACL) reconstruction surgery. Patients and Methods: A total of 90 American Society of Anesthesiologists classes I and II patients who were scheduled to undergo elective ACL reconstruction were enrolled in the study. The patients were randomly allocated to 3 equal groups to receive sonar-guided femoral and sciatic nerve blocks. In Group I, 17 ml of room temperature (20–25°C) 0.5% bupivacaine and 3 ml of room temperature saline were injected for each nerve block whereas in Group II, 17 ml of cold (4°C) 0.5% bupivacaine and 3 ml of cold saline were injected for each nerve block. In Group III, 17 ml of room temperature 0.5% bupivacaine and 3 ml of MgSo4 5% were injected for each nerve block. The onset of sensory and motor block was evaluated every 3 min for 30 min. Surgery was started after complete sensory and motor block were achieved. Intraoperatively, the patients were evaluated for heart rate and mean arterial pressure, rescue analgesic and sedative requirements plus patient and surgeon satisfaction. Postoperatively, hemodynamics, duration of analgesia, resolution of motor block, time to first analgesic, total analgesic consumption, and the incidence of side effects were recorded. Results: There was no statistically significant difference in demographic data, mean arterial pressure, heart rate, and duration of

  10. A comparative study of red and blue light-emitting diodes and low-level laser in regeneration of the transected sciatic nerve after an end to end neurorrhaphy in rabbits.

    PubMed

    Takhtfooladi, Mohammad Ashrafzadeh; Sharifi, Davood

    2015-12-01

    This study aimed at evaluating the effects of red and blue light-emitting diodes (LED) and low-level laser (LLL) on the regeneration of the transected sciatic nerve after an end-to-end neurorrhaphy in rabbits. Forty healthy mature male New Zealand rabbits were randomly assigned into four experimental groups: control, LLL (680 nm), red LED (650 nm), and blue LED (450 nm). All animals underwent the right sciatic nerve neurotmesis injury under general anesthesia and end-to-end anastomosis. The phototherapy was initiated on the first postoperative day and lasted for 14 consecutive days at the same time of the day. On the 30th day post-surgery, the animals whose sciatic nerves were harvested for histopathological analysis were euthanized. The nerves were analyzed and quantified the following findings: Schwann cells, large myelinic axons, and neurons. In the LLL group, as compared to other groups, an increase in the number of all analyzed aspects was observed with significance level (P < 0.05). This finding suggests that postoperative LLL irradiation was able to accelerate and potentialize the peripheral nerve regeneration process in rabbits within 14 days of irradiation.

  11. Effects of sciatic nerve transection on ultrastructure, NADPH-diaphorase reaction and serotonin-, tyrosine hydroxylase-, c-Fos-, glucose transporter 1- and 3-like immunoreactivities in frog dorsal root ganglion.

    PubMed

    Rigon, F; Rossato, D; Auler, V B; Dal Bosco, L; Faccioni-Heuser, M C; Partata, W A

    2013-06-01

    Frogs have been used as an alternative model to study pain mechanisms. Since we did not find any reports on the effects of sciatic nerve transection (SNT) on the ultrastructure and pattern of metabolic substances in frog dorsal root ganglion (DRG) cells, in the present study, 18 adult male frogs (Rana catesbeiana) were divided into three experimental groups: naive (frogs not subjected to surgical manipulation), sham (frogs in which all surgical procedures to expose the sciatic nerve were used except transection of the nerve), and SNT (frogs in which the sciatic nerve was exposed and transected). After 3 days, the bilateral DRG of the sciatic nerve was collected and used for transmission electron microscopy. Immunohistochemistry was used to detect reactivity for glucose transporter (Glut) types 1 and 3, tyrosine hydroxylase, serotonin and c-Fos, as well as nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-diaphorase). SNT induced more mitochondria with vacuolation in neurons, satellite glial cells (SGCs) with more cytoplasmic extensions emerging from cell bodies, as well as more ribosomes, rough endoplasmic reticulum, intermediate filaments and mitochondria. c-Fos immunoreactivity was found in neuronal nuclei. More neurons and SGCs surrounded by tyrosine hydroxylase-like immunoreactivity were found. No change occurred in serotonin- and Glut1- and Glut3-like immunoreactivity. NADPH-diaphorase occurred in more neurons and SGCs. No sign of SGC proliferation was observed. Since the changes of frog DRG in response to nerve injury are similar to those of mammals, frogs should be a valid experimental model for the study of the effects of SNT, a condition that still has many unanswered questions. PMID:23739744

  12. Morphometric and high resolution scanning electron microscopy analysis of low-level laser therapy and latex protein (Hevea brasiliensis) administration following a crush injury of the sciatic nerve in rats.

    PubMed

    Dias, Fernando J; Issa, João Paulo M; Coutinho-Netto, Joaquim; Fazan, Valéria P S; Sousa, Luiz Gustavo; Iyomasa, Mamie M; Papa, Paula C; Watanabe, Ii-Sei

    2015-02-15

    This study evaluated the effect of low-level laser therapy (LLLT; 15 J/cm(2)) and a latex protein (F1) on a crush injury of the sciatic (ischiadicus) nerve. Seventy-two rats (male, 250 g) were divided into 6 groups: CG, control; EG, exposed nerve; IG, injured nerve without treatment; LG, injured nerve with LLLT; HG, injured nerve with F1; and LHG, injured nerve with LLLT and F1. After 4 or 8 weeks, the animals were euthanized and samples of the sciatic nerve were collected for morphometric and high-resolution scanning electron microscopy (HRSEM) analysis. After 4 weeks, the morphometry revealed improvements in the treated animals, and the HG appeared to be the most similar to the CG; after 8 weeks, the injured groups showed improvements compared to the previous period, and the results of the treatment groups were more similar to one another. At HRSEM after 4 weeks, the treated groups were similar and showed improvement compared to the IG; after 8 weeks, the LHG and HG had the best results. In conclusion, the treatments resulted in improvement after the nerve injury, and this recovery was time-dependent. In addition, the use of the F1 resulted in the best morphometric and ultrastructural findings. PMID:25619570

  13. Pseudoradial Nerve Palsy Caused by Acute Ischemic Stroke

    PubMed Central

    Tahir, Hassan; Daruwalla, Vistasp; Meisel, Jeremy; Kodsi, Samir E.

    2016-01-01

    Pseudoperipheral palsy has been used to characterize isolated monoparesis secondary to stroke. Isolated hand nerve palsy is a rare presentation for acute cerebral stroke. Our patient presented with clinical features of typical peripheral radial nerve palsy and a normal computed tomography scan of the head, which, without a detailed history and neurological examination, could have been easily misdiagnosed as a peripheral nerve lesion deferring further investigation for a stroke. We stress the importance of including cerebral infarction as a critical differential diagnosis in patients presenting with sensory-motor deficit in an isolated peripheral nerve pattern. A good history and physical exam can differentiate stroke from peripheral neuropathy as the cause of radial nerve palsy. PMID:27493976

  14. Pseudoradial Nerve Palsy Caused by Acute Ischemic Stroke.

    PubMed

    Tahir, Hassan; Daruwalla, Vistasp; Meisel, Jeremy; Kodsi, Samir E

    2016-01-01

    Pseudoperipheral palsy has been used to characterize isolated monoparesis secondary to stroke. Isolated hand nerve palsy is a rare presentation for acute cerebral stroke. Our patient presented with clinical features of typical peripheral radial nerve palsy and a normal computed tomography scan of the head, which, without a detailed history and neurological examination, could have been easily misdiagnosed as a peripheral nerve lesion deferring further investigation for a stroke. We stress the importance of including cerebral infarction as a critical differential diagnosis in patients presenting with sensory-motor deficit in an isolated peripheral nerve pattern. A good history and physical exam can differentiate stroke from peripheral neuropathy as the cause of radial nerve palsy. PMID:27493976

  15. Expression patterns of T-type Cav3.2 channel and insulin-like growth factor-1 receptor in dorsal root ganglion neurons of mice after sciatic nerve axotomy.

    PubMed

    Lin, Si-Fang; Yu, Xiao-Lu; Liu, Xiao-Ya; Wang, Bing; Li, Cheng-Hui; Sun, Yan-Gang; Liu, Xing-Jun

    2016-10-19

    Substantial evidence indicates that T-type Cav3.2 channel and insulin-like growth factor-1 (IGF-1) contribute to pain hypersensitivity within primary sensory nerves. A recent study suggested that activation of IGF-1 receptor (IGF-1R) could increase Cav3.2 channel currents and further contribute to inflammatory pain sensitivity. However, the expression patterns of Cav3.2 and IGF-1R and their colocalization in dorsal root ganglion (DRG) in chronic neuropathic pain condition remain unknown. In this study, we explored expression patterns of Cav3.2, IGF-1R and their colocalization, and whether phenotypic switch occurs in a subpopulation of Cav3.2 or IGF-1R neurons in mouse DRGs after sciatic nerve axotomy with immunofluorescence, real-time reverse transcription-PCR, and western blot assays. We found that expressions of Cav3.2 and IGF-1R, and their colocalization were not increased in DRGs of mice following axotomy. In addition, Cav3.2 or IGF-1R subpopulation neurons did not acquire significant switch in expression phenotype after sciatic nerve axotomy. Our findings argue for an upregulation of Cav3.2 and IGF-1R expression in lumbar DRGs post-sciatic nerve axotomy and provided an insight for understanding the functions of peripheral afferent Cav3.2 channel and IGF-1/IGF-1R signaling in chronic neuropathic pain. PMID:27571431

  16. Complete sciatic nerve transection induces increase of neuropeptide Y-like immunoreactivity in primary sensory neurons and spinal cord of frogs.

    PubMed

    Guedes, Renata P; Marchi, Melina I; Achaval, Matilde; Partata, Wania A

    2004-12-01

    Neuropeptide Y (NPY) was immunohistochemically investigated in the frog spinal cord and dorsal root ganglia after axotomy. In normal ganglia, moderate NPY-like immunoreactivity (NPY-IR) prevailed in large and medium cells. In the spinal cord, the NPY-IR was densest in the dorsal part of the lateral funiculus. Other fibers and neurons NPY-IR were observed in the dorsal and ventral terminal fields and mediolateral band. NPY-IR fibers were also found in the ventral horn and in the ventral and lateral funiculi. The sciatic nerve transection increased the NPY-IR in large and medium neurons of the ipsilateral and contralateral dorsal root ganglia at 3 and 7 days, but no clear change was found at 15 days. In the spinal cord, there was a bilateral increase in the NPY-IR of the dorsal part of the lateral funiculus. In the ipsilateral side, the NPY-IR was increased at 3 and 7 days but was decreased at 15 days. In the contralateral side, a significant reduction at 15 days occurred. These findings seem to favor the role of NPY in the modulation of pain-related information in frogs, suggesting that this role of NPY may have appeared early in vertebrate evolution.

  17. μ-Conotoxins that differentially block sodium channels NaV1.1 through 1.8 identify those responsible for action potentials in sciatic nerve

    PubMed Central

    Wilson, Michael J.; Yoshikami, Doju; Azam, Layla; Gajewiak, Joanna; Olivera, Baldomero M.; Bulaj, Grzegorz; Zhang, Min-Min

    2011-01-01

    Voltage-gated sodium channels (VGSCs) are important for action potentials. There are seven major isoforms of the pore-forming and gate-bearing α-subunit (NaV1) of VGSCs in mammalian neurons, and a given neuron can express more than one isoform. Five of the neuronal isoforms, NaV1.1, 1.2, 1.3, 1.6, and 1.7, are exquisitely sensitive to tetrodotoxin (TTX), and a functional differentiation of these presents a serious challenge. Here, we examined a panel of 11 μ-conopeptides for their ability to block rodent NaV1.1 through 1.8 expressed in Xenopus oocytes. Although none blocked NaV1.8, a TTX-resistant isoform, the resulting “activity matrix” revealed that the panel could readily discriminate between the members of all pair-wise combinations of the tested isoforms. To examine the identities of endogenous VGSCs, a subset of the panel was tested on A- and C-compound action potentials recorded from isolated preparations of rat sciatic nerve. The results show that the major subtypes in the corresponding A- and C-fibers were NaV1.6 and 1.7, respectively. Ruled out as major players in both fiber types were NaV1.1, 1.2, and 1.3. These results are consistent with immunohistochemical findings of others. To our awareness this is the first report describing a qualitative pharmacological survey of TTX-sensitive NaV1 isoforms responsible for propagating action potentials in peripheral nerve. The panel of μ-conopeptides should be useful in identifying the functional contributions of NaV1 isoforms in other preparations. PMID:21652775

  18. Effects of sciatic nerve transection on glucose uptake in the presence and absence of lactate in the frog dorsal root ganglia and spinal cord.

    PubMed

    Rigon, F; Horst, A; Kucharski, L C; Silva, R S M; Faccioni-Heuser, M C; Partata, W A

    2014-08-01

    Frogs have been used as an alternative model to study pain mechanisms because the simplicity of their nervous tissue and the phylogenetic aspect of this question. One of these models is the sciatic nerve transection (SNT), which mimics the clinical symptoms of "phantom limb", a condition that arises in humans after amputation or transverse spinal lesions. In mammals, the SNT increases glucose metabolism in the central nervous system, and the lactate generated appears to serve as an energy source for nerve cells. An answerable question is whether there is elevated glucose uptake in the dorsal root ganglia (DRG) after peripheral axotomy. As glucose is the major energy substrate for frog nervous tissue, and these animals accumulate lactic acid under some conditions, bullfrogs Lithobates catesbeianus were used to demonstrate the effect of SNT on DRG and spinal cord 1-[14C] 2-deoxy-D-glucose (14C-2-DG) uptake in the presence and absence of lactate. We also investigated the effect of this condition on the formation of 14CO2 from 14C-glucose and 14C-L-lactate, and plasmatic glucose and lactate levels. The 3-O-[14C] methyl-D-glucose (14C-3-OMG) uptake was used to demonstrate the steady-state tissue/medium glucose distribution ratio under these conditions. Three days after SNT, 14C-2-DG uptake increased, but 14C-3-OMG uptake remained steady. The increase in 14C-2-DG uptake was lower when lactate was added to the incubation medium. No change was found in glucose and lactate oxidation after SNT, but lactate and glucose levels in the blood were reduced. Thus, our results showed that SNT increased the glucose metabolism in the frog DRG and spinal cord. The effect of lactate on this uptake suggests that glucose is used in glycolytic pathways after SNT. PMID:25627385

  19. Role of brainstem serotonin in analgesia produced by low-intensity exercise on neuropathic pain after sciatic nerve injury in mice.

    PubMed

    Bobinski, Franciane; Ferreira, Tamara A A; Córdova, Marina M; Dombrowski, Patrícia A; da Cunha, Cláudio; Santo, Caroline C do Espírito; Poli, Anicleto; Pires, Rita G W; Martins-Silva, Cristina; Sluka, Kathleen A; Santos, Adair R S

    2015-12-01

    Physical exercise is a low-cost, safe, and efficient intervention for the reduction of neuropathic chronic pain in humans. However, the underlying mechanisms for how exercise reduces neuropathic pain are not yet well understood. Central monoaminergic systems play a critical role in endogenous analgesia leading us to hypothesize that the analgesic effect of low-intensity exercise occurs through activation of monoaminergic neurotransmission in descending inhibitory systems. To test this hypothesis, we induced peripheral nerve injury (PNI) by crushing the sciatic nerve. The exercise intervention consisted of low-intensity treadmill running for 2 weeks immediately after injury. Animals with PNI showed an increase in pain-like behaviors that were reduced by treadmill running. Reduction of serotonin (5-hydroxytryptamine) synthesis using the tryptophan hydroxylase inhibitor para-chlorophenylalanine methyl ester prevented the analgesic effect of exercise. However, blockade catecholamine synthesis with the tyrosine hydroxylase inhibitor alpha-methyl-para-tyrosine had no effect. In parallel, 2 weeks of exercise increased brainstem levels of the 5-HT and its metabolites (5-hydroxyindoleacetic acid), decreased expression of the serotonin transporter, and increased expression of 5-HT receptors (5HT-1B, 2A, 2C). Finally, PNI-induced increase in inflammatory cytokines, tumor necrosis factor-alpha, and interleukin-1 beta, in the brainstem, was reversed by 2 weeks of exercise. These findings provide new evidence indicating that low-intensity aerobic treadmill exercise suppresses pain-like behaviors in animals with neuropathic pain by enhancing brainstem 5-HT neurotransmission. These data provide a rationale for the analgesia produced by exercise to provide an alternative approach to the treatment of chronic neuropathic pain.

  20. Isolated sciatic neuropathy as an initial manifestation of a high grade B-cell lymphoma: A case report and literature review.

    PubMed

    He, Wenzhuan; Wang, Weizhen; Gustas, Cristy; Malysz, Jozef; Kaur, Divpreet

    2016-10-01

    Sciatic nerve neuropathy due to infiltrating of a high grade B-cell lymphoma is a very rare situation and has not often been reported. We report a case with a previous history of indolent lymphoma who presented with isolated sciatic nerve neuropathy and was found to have diffuse large B cell lymphoma involving the sciatic nerve. Although the current case is not a primary sciatic nerve lymphoma given the systematic involvement shown on MRI and PET/CT scan, the case represents a neurolymphomatosis of the sciatic nerve given the direct invasion of the lymphoma cells into the sciatic nerve. Due to the rarity of this condition, we subsequently reviewed related literatures.

  1. Methylcobalamin promotes the differentiation of Schwann cells and remyelination in lysophosphatidylcholine-induced demyelination of the rat sciatic nerve

    PubMed Central

    Nishimoto, Shunsuke; Tanaka, Hiroyuki; Okamoto, Michio; Okada, Kiyoshi; Murase, Tsuyoshi; Yoshikawa, Hideki

    2015-01-01

    Schwann cells (SCs) are constituents of the peripheral nervous system. The differentiation of SCs in injured peripheral nerves is critical for regeneration after injury. Methylcobalamin (MeCbl) is a vitamin B12 analog that is necessary for the maintenance of the peripheral nervous system. In this study, we estimated the effect of MeCbl on SCs. We showed that MeCbl downregulated the activity of Erk1/2 and promoted the expression of the myelin basic protein in SCs. In a dorsal root ganglion neuron–SC coculture system, myelination was promoted by MeCbl. In a focal demyelination rat model, MeCbl promoted remyelination and motor and sensory functional regeneration. MeCbl promoted the in vitro differentiation of SCs and in vivo myelination in a rat demyelination model and may be a novel therapy for several types of nervous disorders. PMID:26300733

  2. Dixdc1 targets CyclinD1 and p21 via PI3K pathway activation to promote Schwann cell proliferation after sciatic nerve crush.

    PubMed

    Wu, Weijie; Liu, Qingqing; Liu, Yuxi; Yu, Zhaohui; Wang, Youhua

    2016-09-16

    Dixdc1 (DIX domain containing-1), the mammalian homolog of Ccd1 (Coiled-coil-Dishevelled-Axin1), is a protein containing a coiled-coil domain and a Dishevelled-Axin (DIX) domain. As a novel component of the Wnt pathway, Dixdc1 has been reported to be able to promote neural progenitor proliferation and neuronal differentiation via Wnt/β-catenin signaling. But there still remains something unknown about Dixdc1 distribution and functions in the lesion and regeneration of the peripheral nervous system (PNS), so we tried to investigate dynamic changes of Dixdc1 expression in a rat sciatic nerve crush (SNC) model in this study. First of all, we detected SNC-induced increased levels of Dixdc1 in Schwann cells and interestingly identified parallel expression of PCNA (proliferation cell nuclear antigen) with Dixdc1. Besides, we observed up-regulated Dixdc1 during the process of TNF-α-induced Schwann cell proliferation. Also, we discovered that Dixdc1 could promote G1-S phase transition accompanied with the up-regulation of CyclinD1 and down-regulation of p21. More importantly, enhanced effects of Dixdc1 on cell proliferation were confirmed to be associated with PI3K activation. Not only blocking of the PI3K but Dixdc1 knockdown led to significantly decreased ability for proliferation, as well as down-regulation of CyclinD1 and up-regulation of p21. In summary, these data demonstrated that Dixdc1 might participate in Schwann cell proliferation by targeting CyclinD1 and p21 at least partially through the PI3K/AKT activation. PMID:27521891

  3. Toward a Broader View of Ube3a in a Mouse Model of Angelman Syndrome: Expression in Brain, Spinal Cord, Sciatic Nerve and Glial Cells.

    PubMed

    Grier, Mark D; Carson, Robert P; Lagrange, Andre Hollis

    2015-01-01

    Angelman Syndrome (AS) is a devastating neurodevelopmental disorder characterized by developmental delay, speech impairment, movement disorder, sleep disorders and refractory epilepsy. AS is caused by loss of the Ube3a protein encoded for by the imprinted Ube3a gene. Ube3a is expressed nearly exclusively from the maternal chromosome in mature neurons. While imprinting in neurons of the brain has been well described, the imprinting and expression of Ube3a in other neural tissues remains relatively unexplored. Moreover, given the overwhelming deficits in brain function in AS patients, the possibility of disrupted Ube3a expression in the infratentorial nervous system and its consequent disability have been largely ignored. We evaluated the imprinting status of Ube3a in the spinal cord and sciatic nerve and show that it is also imprinted in these neural tissues. Furthermore, a growing body of clinical and radiological evidence has suggested that myelin dysfunction may contribute to morbidity in many neurodevelopmental syndromes. However, findings regarding Ube3a expression in non-neuronal cells of the brain have varied. Utilizing enriched primary cultures of oligodendrocytes and astrocytes, we show that Ube3a is expressed, but not imprinted in these cell types. Unlike many other neurodevelopmental disorders, AS symptoms do not become apparent until roughly 6 to 12 months of age. To determine the temporal expression pattern and silencing, we analyzed Ube3a expression in AS mice at several time points. We confirm relaxed imprinting of Ube3a in neurons of the postnatal developing cortex, but not in structures in which neurogenesis and migration are more complete. This furthers the hypothesis that the apparently normal window of development in AS patients is supported by an incompletely silenced paternal allele in developing neurons, resulting in a relative preservation of Ube3a expression during this crucial epoch of early development. PMID:25894543

  4. Endoscopic Sciatic Neurolysis

    PubMed Central

    Knudsen, Joshua S.; McConkey, Mark O.; Brick, Matthew J.

    2015-01-01

    Despite remaining a controversial diagnosis, piriformis syndrome continues to affect patients' quality of life with pain, sitting discomfort, and exercise intolerance. Open sciatic neurolysis has been noted by the senior author to often only bring temporary relief of the symptoms, with the recurrence presumably due to postoperative scar tissue. Minimally invasive techniques used to decompress the nerve have met with mixed results. This article describes a step-by-step surgical technique designed to maximize patient safety, as well as surgeon orientation, and achieve a thorough neurolysis. Preoperative findings suggestive of piriformis syndrome are described and include retro-trochanteric pain, sciatica-like leg pain, and paresthesias, as well as a positive response to computed tomography–guided injection of dilute ropivacaine hydrochloride and 40 mg of triamcinolone. The operation is performed with the patient in the lateral decubitus position through 2 portals 6 to 8 cm apart, allowing for good triangulation. Dissection is undertaken with a combination of radiofrequency and a laparoscopic peanut, with the assistance of a vascular sling to control the sciatic nerve. Encouraging results have been achieved, and with increasing interest in this procedure, a step-by-step technical description with an accompanying video may prove useful for other experienced hip arthroscopists. Pearls and pitfalls are discussed. PMID:26759776

  5. Sphenoidal mucocele presenting as acute cranial nerve palsies

    PubMed Central

    Cheng, Clarissa S.M.; Sanjay, Srinivasan; Yip, Chee Chew; Yuen, Heng-Wai

    2012-01-01

    Sphenoidal sinus mucoceles are indolent lesions that, when sufficiently large, can compress on the optic canal or superior orbital fissure, rapidly causing loss of vision, optic neuropathy, ptosis, pain, ophthalmoplegia, and diplopia. We herein report a 72-year-old gentleman who presented acutely with Cranial Nerve II, III, and IV palsies secondary to a sphenoidal sinus mucocele that was confirmed on magnetic resonance imaging and successfully treated with endoscopic drainage. This cause of orbital apex syndrome is important for clinicians to know as early diagnosis and treatment is critical in recovering visual potential. PMID:23961035

  6. Relationship of axonal voltage-gated sodium channel 1.8 (NaV1.8) mRNA accumulation to sciatic nerve injury-induced painful neuropathy in rats.

    PubMed

    Ruangsri, Supanigar; Lin, Audrey; Mulpuri, Yatendra; Lee, Kyung; Spigelman, Igor; Nishimura, Ichiro

    2011-11-18

    Painful peripheral neuropathy is a significant clinical problem; however, its pathological mechanism and effective treatments remain elusive. Increased peripheral expression of tetrodotoxin-resistant voltage-gated sodium channel 1.8 (NaV1.8) has been shown to associate with chronic pain symptoms in humans and experimental animals. Sciatic nerve entrapment (SNE) injury was used to develop neuropathic pain symptoms in rats, resulting in increased NaV1.8 mRNA in the injured nerve but not in dorsal root ganglia (DRG). To study the role of NaV1.8 mRNA in the pathogenesis of SNE-induced painful neuropathy, NaV1.8 shRNA vector was delivered by subcutaneous injection of cationized gelatin/plasmid DNA polyplex into the rat hindpaw and its subsequent retrograde transport via sciatic nerve to DRG. This in vivo NaV1.8 shRNA treatment reversibly and repeatedly attenuated the SNE-induced pain symptoms, an effect that became apparent following a distinct lag period of 3-4 days and lasted for 4-6 days before returning to pretreatment levels. Surprisingly, apparent knockdown of NaV1.8 mRNA occurred only in the injured nerve, not in the DRG, during the pain alleviation period. Levels of heteronuclear NaV1.8 RNA were unaffected by SNE or shRNA treatments, suggesting that transcription of the Scn10a gene encoding NaV1.8 was unchanged. Based on these data, we postulate that increased axonal mRNA transport results in accumulation of functional NaV1.8 protein in the injured nerve and the development of painful neuropathy symptoms. Thus, targeted delivery of agents that interfere with axonal NaV1.8 mRNA may represent effective neuropathic pain treatments. PMID:21965668

  7. Effects of Acute Organophosphorus Poisoning on Function of Peripheral Nerves: A Cohort Study

    PubMed Central

    Jayasinghe, Sudheera S.; Pathirana, Kithsiri D.; Buckley, Nick A.

    2012-01-01

    Background Following acute organophosphorus (OP) poisoning patients complain of numbness without objective sensory abnormalities or other features of OP induced delayed polyneuropathy. The aim of this study was to measure peripheral nerve function after acute exposure to OP. Methods A cohort study was conducted with age, gender and occupation matched controls. Motor nerve conduction velocity (MNCV), amplitude and area of compound muscle action potential (CMAP), sensory nerve conduction velocity (SNCV), F- waves and electromyography (EMG) on the deltoid and the first dorsal interosseous muscles on the dominant side were performed, following acute OP poisoning. All neurophysiological assessments except EMG were performed on the controls. Assessments were performed on the day of discharge from the hospital (the first assessment) and six weeks (the second assessment) after the exposure. The controls were assessed only once. Results There were 70 patients (50 males) and 70 controls. Fifty-three patients attended for the second assessment. In the first assessment MNCV of all the motor nerves examined, CMAP amplitude and SNCV of ulnar nerve, median and ulnar F-wave occurrence in the patients were significantly reduced compared to the controls. In the second assessment significant reduction was found in SNCV of both sensory nerves examined, MNCV of ulnar nerve, CMAP amplitude of common peroneal nerve, F-wave occurrence of median and ulnar nerves. No abnormalities were detected in the patients when compared to the standard cut-off values of nerve conduction studies except F-wave occurrence. EMG studies did not show any abnormality. Conclusion There was no strong evidence of irreversible peripheral nerve damage following acute OP poisoning, however further studies are required. PMID:23185328

  8. Effect of oblique nerve grafting on peripheral nerve regeneration in rats.

    PubMed

    Kotulska, Katarzyna; Marcol, Wiesław; Larysz-Brysz, Magdalena; Tendera, Zofia; Malinowska-Kołodziej, Izabela; Slusarczyk, Wojciech; Jedrzejowska-Szypułka, Halina; Lewin-Kowalik, Joanna

    2006-01-01

    Current methods of peripheral nerve repair are to rejoin cut nerve stumps directly or to bridge large gaps with autologous nerve grafts. In both cases the surface of nerve stump endings is typically cut perpendicularly to the long axis of the nerve. The outcome of such operations, however, is still not satisfactory. In this study, we examine the effect of oblique nerve cutting and grafting on morphological as well as functional features of regeneration. In adult rats, sciatic nerve was cut and rejoined either directly or using an autologous graft, at 90 degrees or 30 degrees angle. Functional regeneration was assessed by walking track analysis during 12-week follow-up. Afterwards muscle weight was measured and histological studies were performed. The latter included nerve fibers and Schwann cells counting, as well as visualization of scar formation and epineural fibrosis. Nerves cut obliquely and rejoined showed better functional recovery than perpendicularly transected. Similar effect was observed after oblique grafting when compared to perpendicular one. Numbers of nerve fibers growing into the distal stump of the nerve as well as the number of Schwann cells were significantly higher in obliquely than in perpendicularly operated nerves. Moreover, growing axons were arranged more regularly following oblique treatment. These data indicate that joining or grafting the nerve stumps at acute angle is a more profitable method of nerve repair than the standard procedure performed at right angle. PMID:17066410

  9. Design, fabrication and evaluation of a conforming circumpolar peripheral nerve cuff electrode for acute experimental use.

    PubMed

    Foldes, Emily L; Ackermann, D Michael; Bhadra, Niloy; Kilgore, Kevin L; Bhadra, Narendra

    2011-03-15

    Nerve cuff electrodes are a principle tool of basic and applied electro-neurophysiology studies and are championed for their ability to achieve good nerve recruitment with low thresholds. We describe the design and method of fabrication for a novel circumpolar peripheral nerve electrode for acute experimental use. This cylindrical cuff-style electrode provides approximately 270° of radial electrode contact with a nerve for each of an arbitrary number of contacts, has a profile that allows for simple placement and removal in an acute nerve preparation, and is designed for adjustment of the cylindrical diameter to ensure a close fit on the nerve. For each electrode, the electrical contacts were cut from 25 μm platinum foil as an array so as to maintain their positions relative to each other within the cuff. Lead wires were welded to each intended contact. The structure was then molded in silicone elastomer, after which the individual contacts were electrically isolated. The final electrode was curved into a cylindrical shape with an inner diameter corresponding to that of the intended target nerve. The positions of these contacts were well maintained during the molding and shaping process and failure rates during fabrication due to contact displacements were very low. Established electrochemical measurements were made on one electrode to confirm expected behavior for a platinum electrode and to measure the electrode impedance to applied voltages at different frequencies. These electrodes have been successfully used for nerve stimulation, recording, and conduction block in a number of different acute animal experiments by several investigators.

  10. Ultrasound-guided femoro-sciatic nerve block for post-operative analgesia after below knee orthopaedic surgeries under subarachnoid block: Comparison between clonidine and dexmedetomidine as adjuvants to levobupivacaine

    PubMed Central

    Chaudhary, Sudarshan Kumar; Verma, Ravinder Kumar; Rana, Shelly; Singh, Jai; Gupta, Bhanu; Singh, Yuvraj

    2016-01-01

    Background and Aims: The advent of ultrasonographic-guided techniques has led to increased interest in femoro-sciatic nerve block (FSNB) for lower limb surgeries. α2-agonists have been used recently as adjuvants to local anaesthetics in nerve blocks. We aimed to compare equal doses of clonidine or dexmedetomidine as an adjuvant to levobupivacaine in FSNB for post-operative analgesia. Methods: Ninety patients scheduled to undergo below knee orthopaedic surgeries under subarachnoid block were divided into three groups: Group LL (n = 30) patients received 38 mL of 0.125% levobupivacaine with 2 mL normal saline, Group LD (n = 30) patients received 38 mL of 0.125% levobupivacaine with 0.5 μg/kg dexmedetomidine and Group LC (n = 30) received 38 mL of 0.125% levobupivacaine with 0.5 μg/kg clonidine in saline to make total drug volume of 40 mL. The primary and secondary outcome variables were duration of analgesia and rescue analgesic requirement, verbal rating score respectively. Continuous variables were analysed with analysis of variance or the Kruskal–Wallis test on the basis of data distribution. Categorical variables were analysed with the contingency table analysis and the Fisher's exact test. Results: Duration of analgesia was prolonged with dexmedetomidine (10.17 ± 2.40 h) and clonidine (7.31 ± 1.76 h) as compared to control (4.16 ± 1.04 h, P = 0.00). Significantly lower pain scores were observed in dexmedetomidine group as compared to clonidine up to 8 h post-operatively. Conclusion: Equal doses of clonidine or dexmedetomidine added to levobupivacaine prolonged the duration of analgesia, decreased requirement of rescue analgesia. Dexmedetomidine delays the requirement of rescue analgesics with better pain scores as compared to clonidine. PMID:27512164

  11. Adenoviral-mediated glial cell line-derived neurotrophic factor gene transfer has a protective effect on sciatic nerve following constriction-induced spinal cord injury.

    PubMed

    Chou, An-Kuo; Yang, Ming-Chang; Tsai, Hung-Pei; Chai, Chee-Yin; Tai, Ming-Hong; Kwan, Aij-Li; Hong, Yi-Ren

    2014-01-01

    Neuropathic pain due to peripheral nerve injury may be associated with abnormal central nerve activity. Glial cell-line-derived neurotrophic factor (GDNF) can help attenuate neuropathic pain in different animal models of nerve injury. However, whether GDNF can ameliorate neuropathic pain in the spinal cord dorsal horn (SCDH) in constriction-induced peripheral nerve injury remains unknown. We investigated the therapeutic effects of adenoviral-mediated GDNF on neuropathic pain behaviors, microglial activation, pro-inflammatory cytokine expression and programmed cell death in a chronic constriction injury (CCI) nerve injury animal model. In this study, neuropathic pain was produced by CCI on the ipsilateral SCDH. Mechanical allodynia was examined with von Frey filaments and thermal sensitivity was tested using a plantar test apparatus post-operatively. Target proteins GDNF-1, GDNFRa-1, MMP2, MMP9, p38, phospho-p38, ED1, IL6, IL1β, AIF, caspase-9, cleaved caspase-9, caspase-3, cleaved caspase-3, PARP, cleaved PARP, SPECTRIN, cleaved SPECTRIN, Beclin-1, PKCσ, PKCγ, iNOS, eNOS and nNOS were detected. Microglial activity was measured by observing changes in immunoreactivity with OX-42. NeuN and TUNEL staining were used to reveal whether apoptosis was attenuated by GDNF. Results showed that administrating GDNF began to attenuate both allodynia and thermal hyperalgesia at day 7. CCI-rats were found to have lower GDNF and GDNFRa-1 expression compared to controls, and GDNF re-activated their expression. Also, GDNF significantly down-regulated CCI-induced protein expression except for MMP2, eNOS and nNOS, indicating that the protective action of GDNF might be associated with anti-inflammation and prohibition of microglia activation. Immunocytochemistry staining showed that GDNF reduced CCI-induced neuronal apoptosis. In sum, GDNF enhanced the neurotrophic effect by inhibiting microglia activation and cytokine production via p38 and PKC signaling. GDNF could be a good

  12. Isolated sciatic neuropathy as an initial manifestation of a high grade B-cell lymphoma: A case report and literature review.

    PubMed

    He, Wenzhuan; Wang, Weizhen; Gustas, Cristy; Malysz, Jozef; Kaur, Divpreet

    2016-10-01

    Sciatic nerve neuropathy due to infiltrating of a high grade B-cell lymphoma is a very rare situation and has not often been reported. We report a case with a previous history of indolent lymphoma who presented with isolated sciatic nerve neuropathy and was found to have diffuse large B cell lymphoma involving the sciatic nerve. Although the current case is not a primary sciatic nerve lymphoma given the systematic involvement shown on MRI and PET/CT scan, the case represents a neurolymphomatosis of the sciatic nerve given the direct invasion of the lymphoma cells into the sciatic nerve. Due to the rarity of this condition, we subsequently reviewed related literatures. PMID:27540756

  13. Acute optic nerve sheath fenestration with the free-electron laser

    NASA Astrophysics Data System (ADS)

    Shen, Jin-Hui; Casagrande, Vivien A.; Joos, Karen M.; Shetlar, Debra J.; Robinson, Richard D.; Head, William S.; Mavity-Hudson, Julia A.; Nunnally, Amy H.

    1999-06-01

    Purpose: To determine if the free electron laser (FEL) energy can be delivered to a small space to perform optic nerve sheath fenestration with minimal acute nerve damage. Methods: A 530 mm hollow waveguide probe was designed. Optic nerve sheath fenestration (1.0 mm diameter) was performed in 8 rabbits using either the FEL (4 eyes, 6.45mm, 10 Hz, 2 mJ) or a knife (4 eyes). Within 2 hours following surgery, the animals were perfused with aldehyde fixative. The integrity of the optic nerve and glial response at the site of fenestration were evaluated on tissue selections with H&E, and antibodies to S100β or GFAP. Results: Surgery using the FEL probe was found to be technically superior to the knife. The glial reaction was limited to a zone adjacent to the fenestration and was similar in both the FEL and knife incisions. Conclusions: The FEL appears capable of efficiently performing an optic nerve sheath fenestration in a small space with minimal acute damage. Both the FEL and knife incisions result in a rapid glial response at the site of fenestration even when optic nerve integrity is not compromised.

  14. Myelination and nodal formation of regenerated peripheral nerve fibers following transplantation of acutely prepared olfactory ensheathing cells.

    PubMed

    Dombrowski, Mary A; Sasaki, Masanori; Lankford, Karen L; Kocsis, Jeffery D; Radtke, Christine

    2006-12-13

    Transplantation of olfactory ensheathing cells (OECs) into injured spinal cord results in improved functional outcome. Mechanisms suggested to account for this functional improvement include axonal regeneration, remyelination and neuroprotection. OECs transplanted into transected peripheral nerve have been shown to modify peripheral axonal regeneration and functional outcome. However, little is known of the detailed integration of OECs at the transplantation site in peripheral nerve. To address this issue, cell populations enriched in OECs were isolated from the olfactory bulbs of adult green fluorescent protein (GFP)-expressing transgenic rats and transplanted into a sciatic nerve crush lesion which transects all axons. Five weeks to 6 months after transplantation, the nerves were studied histologically. GFP-expressing OECs survived in the lesion and distributed longitudinally across the lesion zone. The internodal regions of individual teased fibers distal to the transection site were characterized by GFP expression in the cytoplasmic and nuclear compartments of cells surrounding the axons. Immunoelectron microscopy for GFP indicated that the transplanted OECs formed peripheral type myelin. Immunostaining for sodium channel and Caspr revealed a high density of Na(v)1.6 at the newly formed nodes of Ranvier which were flanked by paranodal Caspr staining. These results indicate that transplanted OECs extensively integrate into transected peripheral nerve and form myelin on regenerated peripheral nerve fibers, and that nodes of Ranvier of these axons display proper sodium channel organization. PMID:17112480

  15. [A case of Ramsey Hunt syndrome with multiple cranial nerve paralysis and acute respiratory failure].

    PubMed

    Sato, K; Nakamura, S; Koseki, T; Yamauchi, F; Baba, M; Mikami, M; Kobayashi, R; Fujikawa, T; Nagaoka, S

    1991-08-01

    The authors report a 56-year-old woman with Ramsey Hunt syndrome with multiple cranial nerve paralysis and acute respiratory failure. Five days before admission, she experienced right otalgia and right facial pain and consulted an otolaryngologist of our hospital, who diagnosed the illness as acute parotitis and laryngopharyngitis. One day before admission, she experienced mild dyspnea and general fatigue and came to our hospital emergency room. A chest X-ray film revealed no abnormalities but some blisters were observed around her right ear. The next day, her dyspnea became more severe and she was admitted. A chest X-ray film on admission revealed right lower lobe consolidation, and neurological examination disclosed multiple cranial nerve paralysis, i.e., paralysis of the right fifth, seventh, eighth, ninth, tenth, eleventh, twelfth and left tenth cranial nerve. The serum titer of anti-herpes zoster antibody was elevated to 1,024, and the patient was diagnosed as having Ramsey Hunt syndrome with multiple cranial nerve paralysis. Arterial blood gas analysis revealed hypoxemia with hypercapnea, which was considered to be due to aspiration pneumonia and central airway obstruction caused by vocal cord paralysis. Mechanical ventilation was soon instituted and several antibiotics and acyclovir were administered intravenously, with marked effects. Three months after admission, the patient was discharged with no sequelae except mild hoarseness. Patients with herpes zoster oticus, facial nerve paralysis and auditory symptoms are diagnosed as having Ramsey Hunt syndrome. This case was complicated by lower cranial nerve paralysis and acute respiratory failure, which is very rare.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. Neuropathological and neuroprotective features of vitamin B12 on the dorsal spinal ganglion of rats after the experimental crush of sciatic nerve: an experimental study

    PubMed Central

    2013-01-01

    Background Spinal motoneuron neuroprotection by vitaminB12 was previously reported; the present study was carried out to evaluate neuroprotectivity in the dorsal root ganglion sensory neuron. Methods In present study thirty-six Wister-Albino rats (aged 8–9 weeks and weighing 200–250 g) were tested. The animals were randomly divided into 6 groups which every group contained 6 rats. Group A: received normal saline (for 42 days); Group B: vitamin B12 was administered (0.5 mg/kg/day for 21 days); Group C: received vitamin B12 (1 mg/kg/day for 21days); Group D: received vitamin B12 (0.5 mg/kg/day for 42 days); Group E; received vitamin B12 (1 mg/kg/day for 42 days); Group F; received no treatment. The L5 Dorsal Root Ganglion (DRG) neurons count compared to the number of left and right neurons .Furthermore, DRG sensory neurons for regeneration were evaluated 21 or 42 days after injury (each group was analyzed by One-Way ANOVA test). Results (1): The comparison of left crushed neurons (LCN) number with right non-crushed neurons in all experimental groups (B, C, D and C), indicating a significant decline in their neurons enumeration (p<0/05). (2): The comparison of test group’s LCN with the control group’s LCN revealed a significant rise in the number of experimental group neurons (p<0/05). (3): Moreover, comparing the number of right neurons in experimental groups with the number of neurons in crushed neurons indicated that the average number of right neurons showed a significant increase in experimental groups (p<0/05). Conclusion Consequently, the probability of nerve regeneration will be increased by the increment of the administered drug dosage and duration. On the other hand, the regeneration and healing in Dorsal Spinal Ganglion will be improved by increase of administration time and vitamin B12 dose, indicating that such vitamin was able to progress recovery process of peripheral nerves damage in experimental rats. Finally, our results have important

  17. Successful treatment of Raynaud’s syndrome in a lupus patient with continuous bilateral popliteal sciatic nerve blocks: a case report

    PubMed Central

    Dao, Thuan; Amaro-Driedger, David; Mehta, Jaideep

    2016-01-01

    Raynaud’s syndrome has been treated medically and invasively, sometimes with regional anesthesia leading up to sympathectomy. We demonstrate that regional anesthesia was in this case a useful technique that can allow some patients to find temporary but significant relief from symptoms of Raynaud’s syndrome exacerbation. We present a 43-year-old woman with Raynaud’s syndrome secondary to lupus who was treated with bilateral popliteal nerve block catheters for ischemic pain and necrosis of her feet; this led to almost immediate resolution of her pain and return of color and function of her feet. While medical management should continue to be a front-line treatment for Raynaud’s syndrome, regional anesthesia can be useful in providing rapid dissipation of symptoms and may thus serve as a viable option for short-term management of this syndrome. PMID:27366104

  18. Optic Nerve Diffusion Tensor Imaging after Acute Optic Neuritis Predicts Axonal and Visual Outcomes

    PubMed Central

    van der Walt, Anneke; Kolbe, Scott C.; Wang, Yejun E.; Klistorner, Alexander; Shuey, Neil; Ahmadi, Gelareh; Paine, Mark; Marriott, Mark; Mitchell, Peter; Egan, Gary F.; Butzkueven, Helmut; Kilpatrick, Trevor J.

    2013-01-01

    Background Early markers of axonal and clinical outcomes are required for early phase testing of putative neuroprotective therapies for multiple sclerosis (MS). Objectives To assess whether early measurement of diffusion tensor imaging (DTI) parameters (axial and radial diffusivity) within the optic nerve during and after acute demyelinating optic neuritis (ON) could predict axonal (retinal nerve fibre layer thinning and multi-focal visual evoked potential amplitude reduction) or clinical (visual acuity and visual field loss) outcomes at 6 or 12 months. Methods Thirty-seven patients presenting with acute, unilateral ON were studied at baseline, one, three, six and 12 months using optic nerve DTI, clinical and paraclinical markers of axonal injury and clinical visual dysfunction. Results Affected nerve axial diffusivity (AD) was reduced at baseline, 1 and 3 months. Reduced 1-month AD correlated with retinal nerve fibre layer (RNFL) thinning at 6 (R=0.38, p=0.04) and 12 months (R=0.437, p=0.008) and VEP amplitude loss at 6 (R=0.414, p=0.019) and 12 months (R=0.484, p=0.003). AD reduction at three months correlated with high contrast visual acuity at 6 (ρ = -0.519, p = 0.001) and 12 months (ρ = -0.414, p=0.011). The time-course for AD reduction for each patient was modelled using a quadratic regression. AD normalised after a median of 18 weeks and longer normalisation times were associated with more pronounced RNFL thinning and mfVEP amplitude loss at 12 months. Affected nerve radial diffusivity (RD) was unchanged until three months, after which time it remained elevated. Conclusions These results demonstrate that AD reduces during acute ON. One month AD reduction correlates with the extent of axonal loss and persistent AD reduction at 3 months predicts poorer visual outcomes. This suggests that acute ON therapies that normalise optic nerve AD by 3 months could also promote axon survival and improve visual outcomes. PMID:24386285

  19. Acute optic nerve sheath fenestration in humans using the free electron laser (FEL): a case report

    NASA Astrophysics Data System (ADS)

    Joos, Karen M.; Mawn, Louise A.; Shen, Jin-Hui; Jansen, E. Duco; Casagrande, Vivien A.

    2002-06-01

    Our previous studies using rabbits and monkeys showed that the Amide II wavelength (6.45 micrometers ) produced by the FEL could efficiently produce an optic nerve sheath fenestration with minimal damage. In order to determine if the technology safely could be applied to human surgery, we used 2 blind human eyes during enucleation to compare the results of producing fenestrations with the FEL or a scissors. FDA and Vanderbilt IRB approvals, and individual patient consents were obtained. The FEL energy was transmitted to a human operating room. After disinsertion of the medial rectus muscle, an optic nerve sheath fenestration (2 mm diameter) was made with either the FEL (6.45 micrometers , 325 micrometers spot size, 30 Hz, 3 mJ) through a hollow waveguide surgical probe or with a scissors. The enucleation was then completed. The optic nerve was dissected from the globe and fixed. Specimens were examined histologically. Dural incisions were effective with both methods. FEL energy at 6.45 micrometers can be transmitted to an operating room and delivered to human ocular tissue through a hollow waveguide surgical probe. This FEL wavelength can produce an optic nerve sheath fenestration without acute direct damage to the nerve in this case report.

  20. Continuous positive airway pressure with pressure support ventilation is effective in treating acute-onset bilateral recurrent laryngeal nerve palsy.

    PubMed

    Leung, Yiuka; Fikry, Karim; Shah, Bhavika; Madapu, Manokanth; Gaz, Randall D; Leffert, Lisa R; Jiang, Yandong

    2015-06-01

    Acute bilateral recurrent laryngeal nerve injury leading to acute vocal cord paralysis (VCP) is a serious complication of head and neck surgery, often requiring emergent surgical intervention. Although well documented, its presentation may be sudden and unexpected, occurring despite lack of obvious intraoperative nerve injury. There is limited literature on airway management strategies for patients with acute bilateral VCP before attaining a secure airway. We report a case of acute VCP that was successfully treated with continuous positive airway pressure via facemask ventilation. This effective temporizing strategy allowed clinicians to plan and prepare for tracheostomy, minimizing potential complications.

  1. Behavioral and electrophysiological recovery following cryogenic nerve injury.

    PubMed

    Kalichman, M W; Myers, R R

    1987-06-01

    Postthoracotomy pain can be reduced by cryoanalgesia of intercostal nerves. The technique involves focal freezing of peripheral nerves to interrupt pain pathways, producing immediate functional changes that recover as the nerves regenerate. To assess the time-course of functional changes that follow nerve injury, unilateral freeze lesions of sciatic nerve were induced in rats with a cryosurgical unit. The contralateral nerves were used as sham-operated controls. Following nerve injury, behavioral and electrophysiologic tests were repeated to 90 days. The acute effect of nerve injury was a decrease in behavioral measures of hind limb function (P less than 0.05), an increase in electrical threshold to elicit hind limb contraction (P less than 0.005), and an absence of stimulus-evoked compound action potential (P less than 0.005). Morphologic changes included substantial endoneurial edema associated with Wallerian degeneration. Remyelination occurred subsequently during the following 35 days. Although all physiologic measures returned toward normal, nerve conduction velocities were still much slower in the experimental group. In a second study, the long-term effects of cryogenic injury were compared with neurolytic injury with 10% procaine HCl, both of which produced a conduction velocity deficit that persisted at least 90 days after the initial injury. These behavioral and electrophysiologic results complement previous reports of morphologic deficits in the nerves including incomplete recovery of nerve fiber diameter and increased thickness of the perineurial sheath. PMID:3582553

  2. Carotid sinus nerve section and the increase in plasma cortisol during acute hypoxia in fetal sheep.

    PubMed Central

    Giussani, D A; McGarrigle, H H; Moore, P J; Bennet, L; Spencer, J A; Hanson, M A

    1994-01-01

    1. We studied the effects of acute isocapnic hypoxia on plasma concentrations of adrenocorticotrophic hormone (ACTH) and cortisol in sixteen sheep fetuses at 118-125 days of gestation (term is 147 days). Eight fetuses had their carotid sinus nerves cut (denervation); the remaining eight had these nerves left intact. 2. There were no differences in the plasma concentrations of ACTH or cortisol between intact and denervated fetuses during normoxia. 3. Whilst plasma cortisol increased in early (after 15 min) and late (after 45 min) hypoxia in intact fetuses, the rise in cortisol in denervated fetuses was delayed, increasing significantly only by late hypoxia. 4. In contrast, plasma ACTH concentrations were increased in early and late hypoxia in both intact and denervated fetuses. The rise was smaller in denervated fetuses, but was not significantly different from that in intact fetuses. 5. Our results indicate that, in the sheep fetus, carotid sinus nerve section delays the rise in plasma cortisol in response to acute hypoxia without affecting the ACTH response. Further work is needed to establish the mechanism underlying this effect of denervation. PMID:8071889

  3. [Diagnostics and treatment of acute odontogenic osteomyelitis of the mandible considering functional state of inferior alveolar nerve].

    PubMed

    Malanchuk, V A; Pavlovskiĭ, L L

    2013-01-01

    Evaluation of functional impairment of inferior alveolar nerve in acute odontogenic inflammatory processes was carried out in this clinical study by means of stimulation electroneurography. Possibility of early diagnosis of acute odontogenic osteomyelitis by this method and effectiveness of decompression osteoperforation for its treatment was shown.

  4. Microglia and monocytes synergistically promote the transition from acute to chronic pain after nerve injury

    PubMed Central

    Peng, Jiyun; Gu, Nan; Zhou, Lijun; B Eyo, Ukpong; Murugan, Madhuvika; Gan, Wen-Biao; Wu, Long-Jun

    2016-01-01

    Microglia and peripheral monocytes contribute to hypersensitivity in rodent models of neuropathic pain. However, the precise respective function of microglia and peripheral monocytes has not been investigated in these models. To address this question, here we combined transgenic mice and pharmacological tools to specifically and temporally control the depletion of microglia and monocytes in a mouse model of spinal nerve transection (SNT). We found that although microglia and monocytes are required during the initiation of mechanical allodynia or thermal hyperalgesia, these cells may not be as important for the maintenance of hypersensitivity. Moreover, we demonstrated that either resident microglia or peripheral monocytes are sufficient in gating neuropathic pain after SNT. We propose that resident microglia and peripheral monocytes act synergistically to initiate hypersensitivity and promote the transition from acute to chronic pain after peripheral nerve injury. PMID:27349690

  5. Demonstrating Electrical Activity in Nerve and Muscle. Part II

    ERIC Educational Resources Information Center

    Robinson, D. J.

    1976-01-01

    Describes the construction of an amplifier and force transducer that can be used to demonstrate electrical activity in nerve and muscle using the gastrocnemius muscle and sciatic nerve of the frog. (MLH)

  6. Peripheral nerve injuries in the athlete.

    PubMed

    Feinberg, J H; Nadler, S F; Krivickas, L S

    1997-12-01

    outcome. Proximal nerve injuries have a poorer prognosis for neurological recovery. The most common peripheral nerve injury in the athlete is the burner syndrome. Though primarily a football injury, burners have been reported in wrestling, hockey, basketball and weight-lifting as a result of acute head, neck and/or shoulder trauma. Most burners are self-limiting, but they occasionally produce permanent neurological deficits. The axillary nerve is commonly injured with shoulder dislocations but is also susceptible to injury by direct compression. The sciatic and common peroneal nerves can be injured by trauma. The suprascapular, musculocutaneous, ulnar, median and tibial nerves are susceptible to entrapment. The long thoracic and femoral nerves can be injured by severe traction.

  7. Interaction of inactivity and nerve breakdown products in the origin of acute denervation changes in rat skeletal muscle.

    PubMed Central

    Cangiano, A; Magherini, P C; Pasino, E; Pellegrino, M; Risaliti, R

    1984-01-01

    The action of nerve breakdown products on innervated fibres of soleus and extensor digitorum longus muscles was investigated with the following procedures: partial denervation, sensory or sympathetic denervation, section of a previously transplanted foreign nerve. Each procedure was performed either in isolation or combined with chronic muscle inactivity obtained by blocking impulse conduction along the sciatic nerve. Silastic cuffs containing tetrodotoxin (TTX) and sodium chloride were utilized for the block. Partial denervation induced extrajunctional sensitivity to acetylcholine (ACh) and resistance to tetrodotoxin not only in the denervated but also in the innervated fibres. The effects in the innervated fibres were equal in magnitude to those in the denervated fibres, provided they were paralysed. The onset of the membrane changes was synchronous in the two classes of fibres and their amount correlated with the extent of partial denervation. If the innervated fibres were normally active, the membrane changes were still detectable, but considerably smaller than in the denervated fibres. Sensory denervation (removal of dorsal root ganglia L4 and L5) was followed by the development of moderate ACh supersensitivity and TTX resistance in chronically paralysed muscles. Furthermore, section of radicular nerves (total denervation, i.e. efferent plus afferent) induced larger membrane changes than those observed following section of ventral roots alone (efferent denervation). Sympathetic denervation was ineffective even when associated with chronic muscle paralysis. Section of a previously transplanted mixed nerve (superficial fibular) was ineffective if the soleus muscle was normally active, while it induced marked extrajunctional ACh sensitivity and TTX resistance when combined with chronic paralysis of the muscle. Section of a transplanted sensory nerve (sural) also induced extrajunctional membrane changes in paralysed soleus muscles, but their magnitude was much

  8. Comprehensive Evaluation of Peripheral Nerve Regeneration in the Acute Healing Phase Using Tissue Clearing and Optical Microscopy in a Rodent Model

    PubMed Central

    Keating, Cameron P.; Senthil-Kumar, Prabhu; Zhao, Jie; Randolph, Mark A.; Winograd, Jonathan M.; Evans, Conor L.

    2014-01-01

    Peripheral nerve injury (PNI), a common injury in both the civilian and military arenas, is usually associated with high healthcare costs and with patients enduring slow recovery times, diminished quality of life, and potential long-term disability. Patients with PNI typically undergo complex interventions but the factors that govern optimal response are not fully characterized. A fundamental understanding of the cellular and tissue-level events in the immediate postoperative period is essential for improving treatment and optimizing repair. Here, we demonstrate a comprehensive imaging approach to evaluate peripheral nerve axonal regeneration in a rodent PNI model using a tissue clearing method to improve depth penetration while preserving neural architecture. Sciatic nerve transaction and end-to-end repair were performed in both wild type and thy-1 GFP rats. The nerves were harvested at time points after repair before undergoing whole mount immunofluorescence staining and tissue clearing. By increasing the optic depth penetration, tissue clearing allowed the visualization and evaluation of Wallerian degeneration and nerve regrowth throughout entire sciatic nerves with subcellular resolution. The tissue clearing protocol did not affect immunofluorescence labeling and no observable decrease in the fluorescence signal was observed. Large-area, high-resolution tissue volumes could be quantified to provide structural and connectivity information not available from current gold-standard approaches for evaluating axonal regeneration following PNI. The results are suggestive of observed behavioral recovery in vivo after neurorrhaphy, providing a method of evaluating axonal regeneration following repair that can serve as an adjunct to current standard outcomes measurements. This study demonstrates that tissue clearing following whole mount immunofluorescence staining enables the complete visualization and quantitative evaluation of axons throughout nerves in a PNI model

  9. A refined technique for sciatic denervation in a golden-mantled ground squirrel (Callospermophilus lateralis) model of disuse atrophy.

    PubMed

    Sarukhanov, Valeri; Van Andel, Roger; Treat, Michael D; Utz, Jenifer C; van Breukelen, Frank

    2014-06-01

    Disuse atrophy of both muscle and bone can occur rapidly during periods of inactivity. In several rodent models developed for the study of disuse atrophy, immobilization is induced by prolonged cage restraint, hind limb unloading, tenotomy, sciatic nerve block or sciatic denervation. In less tractable species such as wild-caught hibernating rodents, the sciatic denervation model is superior in terms of both animal welfare and applicability to the characteristics of natural cases of disuse atrophy. The authors describe a refined surgical approach to sciatic denervation in golden-mantled ground squirrels (Callospermophilus lateralis), a hibernating species, that improves animal welfare and reduces the incidence of post-operative complications such as autotomy.

  10. Effects of acute administration of selective serotonin reuptake inhibitors on sympathetic nerve activity.

    PubMed

    Tiradentes, R V; Pires, J G P; Silva, N F; Ramage, A G; Santuzzi, C H; Futuro Neto, H A

    2014-07-01

    Serotonergic mechanisms have an important function in the central control of circulation. Here, the acute effects of three selective serotonin (5-HT) reuptake inhibitors (SSRIs) on autonomic and cardiorespiratory variables were measured in rats. Although SSRIs require 2-3 weeks to achieve their full antidepressant effects, it has been shown that they cause an immediate inhibition of 5-HT reuptake. Seventy male Wistar rats were anesthetized with urethane and instrumented to record blood pressure, heart rate, renal sympathetic nerve activity (RSNA), and respiratory frequency. At lower doses, the acute cardiovascular effects of fluoxetine, paroxetine and sertraline administered intravenously were insignificant and variable. At middle and higher doses, a general pattern was observed, with significant reductions in sympathetic nerve activity. At 10 min, fluoxetine (3 and 10 mg/kg) reduced RSNA by -33 ± 4.7 and -31 ± 5.4%, respectively, without changes in blood pressure; 3 and 10 mg/kg paroxetine reduced RSNA by -35 ± 5.4 and -31 ± 5.5%, respectively, with an increase in blood pressure +26.3 ± 2.5; 3 mg/kg sertraline reduced RSNA by -59.4 ± 8.6%, without changes in blood pressure. Sympathoinhibition began 5 min after injection and lasted approximately 30 min. For fluoxetine and sertraline, but not paroxetine, there was a reduction in heart rate that was nearly parallel to the sympathoinhibition. The effect of these drugs on the other variables was insignificant. In conclusion, acute peripheral administration of SSRIs caused early autonomic cardiovascular effects, particularly sympathoinhibition, as measured by RSNA. Although a peripheral action cannot be ruled out, such effects are presumably mostly central. PMID:25003632

  11. Effects of acute selective pudendal nerve electrical stimulation after simulated childbirth injury

    PubMed Central

    Gill, Bradley C.; Dissaranan, Charuspong; Zutshi, Massarat; Balog, Brian M.; Lin, Danli; Damaser, Margot S.

    2013-01-01

    During childbirth, a combinatorial injury occurs and can result in stress urinary incontinence (SUI). Simulated childbirth injury, consisting of vaginal distension (VD) and pudendal nerve crush (PNC), results in slowed recovery of continence, as well as decreased expression of brain-derived neurotrophic factor (BDNF), a regenerative cytokine. Electrical stimulation has been shown to upregulate BDNF in motor neurons and facilitate axon regrowth through the increase of βII-tubulin expression after injury. In this study, female rats underwent selective pudendal nerve motor branch (PNMB) stimulation after simulated childbirth injury or sham injury to determine whether such stimulation affects bladder and anal function after injury and whether the stimulation increases BDNF expression in Onuf's nucleus after injury. Rats received 4 h of VD followed by bilateral PNC and 1 h of subthreshold electrical stimulation of the left PNMB and sham stimulation of the right PNMB. Rats underwent filling cystometry and anal pressure recording before, during, and after the stimulation. Bladder and anal contractile function were partially disrupted after injury. PNMB stimulation temporarily inhibited bladder contraction after injury. Two days and 1 wk after injury, BDNF expression in Onuf's nucleus of the stimulated side was significantly increased compared with the sham-stimulated side, whereas βII-tubulin expression in Onuf's nucleus of the stimulated side was significantly increased only 1 wk after injury. Acute electrical stimulation of the pudendal nerve proximal to the crush site upregulates BDNF and βII-tubulin in Onuf's nucleus after simulated childbirth injury, which could be a potential preventive option for SUI after childbirth injury. PMID:23152293

  12. Acute Myeloid Leukemia Relapse Presenting as Complete Monocular Vision Loss due to Optic Nerve Involvement

    PubMed Central

    2016-01-01

    Acute myeloid leukemia (AML) involvement of the central nervous system is relatively rare, and detection of leptomeningeal disease typically occurs only after a patient presents with neurological symptoms. The case herein describes a 48-year-old man with relapsed/refractory AML of the mixed lineage leukemia rearrangement subtype, who presents with monocular vision loss due to leukemic eye infiltration. MRI revealed right optic nerve sheath enhancement and restricted diffusion concerning for nerve ischemia and infarct from hypercellularity. Cerebrospinal fluid (CSF) analysis showed a total WBC count of 81/mcl with 96% AML blasts. The onset and progression of visual loss were in concordance with rise in peripheral blood blast count. A low threshold for diagnosis of CSF involvement should be maintained in patients with hyperleukocytosis and high-risk cytogenetics so that prompt treatment with whole brain radiation and intrathecal chemotherapy can be delivered. This case suggests that the eye, as an immunoprivileged site, may serve as a sanctuary from which leukemic cells can resurge and contribute to relapsed disease in patients with high-risk cytogenetics. PMID:27668104

  13. Acute Myeloid Leukemia Relapse Presenting as Complete Monocular Vision Loss due to Optic Nerve Involvement

    PubMed Central

    2016-01-01

    Acute myeloid leukemia (AML) involvement of the central nervous system is relatively rare, and detection of leptomeningeal disease typically occurs only after a patient presents with neurological symptoms. The case herein describes a 48-year-old man with relapsed/refractory AML of the mixed lineage leukemia rearrangement subtype, who presents with monocular vision loss due to leukemic eye infiltration. MRI revealed right optic nerve sheath enhancement and restricted diffusion concerning for nerve ischemia and infarct from hypercellularity. Cerebrospinal fluid (CSF) analysis showed a total WBC count of 81/mcl with 96% AML blasts. The onset and progression of visual loss were in concordance with rise in peripheral blood blast count. A low threshold for diagnosis of CSF involvement should be maintained in patients with hyperleukocytosis and high-risk cytogenetics so that prompt treatment with whole brain radiation and intrathecal chemotherapy can be delivered. This case suggests that the eye, as an immunoprivileged site, may serve as a sanctuary from which leukemic cells can resurge and contribute to relapsed disease in patients with high-risk cytogenetics.

  14. Acute effects of neural mobilization and infrared on the mechanics of the median nerve

    PubMed Central

    Nunes, Monara Kedma; Fontenele dos Santos, Gabrielly; Martins e Silva, Diandra Caroline; Mota de Freitas, Ana Cláudia; Henriques, Isadora Ferreira; Andrade, Peterson Marco; Machado, Dionis de Castro; Teixeira, Silmar; Neves, Marco Orsini; Dias, Gildário; Silva-Júnior, Fernando; Bastos, Victor Hugo

    2016-01-01

    [Purpose] This study analyzed the acute effects of infrared and neural mobilization on the median nerve on the range of elbow extension of the dominant limb. [Subjects and Methods] Forty participants from university, neurologically asymptomatic, 12 males and 28 females (22.8 ± 1.9 years), were randomly divided into four groups: Group 1 (control) rested for 25 minutes in the supine position; Group 2 received the specific neural mobilization for the median nerve; Group 3 received an application of infrared for 15 minutes on the forearm; Group 4 received the same application of infrared followed by neural mobilization. The goniometric parameters of elbow extension were evaluated after the intervention. [Results] Significant differences of extension value were observed between Group 1 and Group 3 (15.75 degrees), and between Group 1 and Group 4 (14.60 degrees), and the average higher in Group 3 (26.35 degrees). [Conclusion] This research provides new experimental evidence that NM in relation to superficial heat produces an immediate effect on elbow range of motion versus NM isolated. PMID:27390402

  15. Acute Myeloid Leukemia Relapse Presenting as Complete Monocular Vision Loss due to Optic Nerve Involvement.

    PubMed

    Patel, Shyam A

    2016-01-01

    Acute myeloid leukemia (AML) involvement of the central nervous system is relatively rare, and detection of leptomeningeal disease typically occurs only after a patient presents with neurological symptoms. The case herein describes a 48-year-old man with relapsed/refractory AML of the mixed lineage leukemia rearrangement subtype, who presents with monocular vision loss due to leukemic eye infiltration. MRI revealed right optic nerve sheath enhancement and restricted diffusion concerning for nerve ischemia and infarct from hypercellularity. Cerebrospinal fluid (CSF) analysis showed a total WBC count of 81/mcl with 96% AML blasts. The onset and progression of visual loss were in concordance with rise in peripheral blood blast count. A low threshold for diagnosis of CSF involvement should be maintained in patients with hyperleukocytosis and high-risk cytogenetics so that prompt treatment with whole brain radiation and intrathecal chemotherapy can be delivered. This case suggests that the eye, as an immunoprivileged site, may serve as a sanctuary from which leukemic cells can resurge and contribute to relapsed disease in patients with high-risk cytogenetics. PMID:27668104

  16. Angiotensin and thromboxane in the enhanced renal adrenergic nerve sensitivity of acute renal failure.

    PubMed Central

    Robinette, J B; Conger, J D

    1990-01-01

    The roles of intrarenal angiotensin (A) and thromboxane (TX) in the vascular hypersensitivity to renal nerve stimulation (RNS) and paradoxical vasoconstriction to renal perfusion pressure (RPP) reduction in the autoregulatory range in 1 wk norepinephrine (NE)-induced acute renal failure (ARF) in rats were investigated. Renal blood flow (RBF) responses were determined before and during intrarenal infusion of an AII and TXA2 antagonist. Saralasin or SQ29548 alone partially corrected the slopes of RBF to RNS and RPP reduction in NE-ARF rats (P less than 0.02). Saralasin + SQ29548 normalized the RBF response to RNS. While combined saralasin + SQ29548 eliminated the vasoconstriction to RPP reduction, similar to the effect of renal denervation, appropriate vasodilatation was not restored. Renal vein norepinephrine efflux during RNS was disproportionately increased in NE-ARF (P less than 0.001) and was suppressed by saralasin + SQ29548 infusion (P less than 0.005). It is concluded that the enhanced sensitivity to RNS and paradoxical vasoconstriction to RPP reduction in 1 wk NE-ARF kidneys are the result of intrarenal TX and AII acceleration of neurotransmitter release to adrenergic nerve activity. PMID:2243129

  17. The role of intercostal nerve preservation in acute pain control after thoracotomy*

    PubMed Central

    Marchetti-Filho, Marco Aurélio; Leão, Luiz Eduardo Villaça; Costa-Junior, Altair da Silva

    2014-01-01

    OBJECTIVE: To evaluate whether the acute pain experienced during in-hospital recovery from thoracotomy can be effectively reduced by the use of intraoperative measures (dissection of the neurovascular bundle prior to the positioning of the Finochietto retractor and preservation of the intercostal nerve during closure). METHODS: We selected 40 patients who were candidates for elective thoracotomy in the Thoracic Surgery Department of the Federal University of São Paulo/Paulista School of Medicine, in the city of São Paulo, Brazil. The patients were randomized into two groups: conventional thoracotomy (CT, n = 20) and neurovascular bundle preservation (NBP, n = 20). All of the patients underwent thoracic epidural anesthesia and muscle-sparing thoracotomy. Pain intensity was assessed with a visual analog scale on postoperative days 1, 3, and 5, as well as by monitoring patient requests for/consumption of analgesics. RESULTS: On postoperative day 5, the self-reported pain intensity was significantly lower in the NBP group than in the CT group (visual analog scale score, 1.50 vs. 3.29; p = 0.04). No significant differences were found between the groups regarding the number of requests for/consumption of analgesics. CONCLUSIONS: In patients undergoing thoracotomy, protecting the neurovascular bundle prior to positioning the retractor and preserving the intercostal nerve during closure can minimize pain during in-hospital recovery. PMID:24831401

  18. Arterial baroreflex control of sympathetic nerve activity during acute hypotension: effect of fitness

    NASA Technical Reports Server (NTRS)

    Fadel, P. J.; Stromstad, M.; Hansen, J.; Sander, M.; Horn, K.; Ogoh, S.; Smith, M. L.; Secher, N. H.; Raven, P. B.

    2001-01-01

    We examined arterial baroreflex control of muscle sympathetic nerve activity (MSNA) during abrupt decreases in mean arterial pressure (MAP) and evaluated whether endurance training alters baroreflex function. Acute hypotension was induced nonpharmacologically in 14 healthy subjects, of which 7 were of high fitness (HF) and 7 were of average fitness (AF), by releasing a unilateral arterial thigh cuff after 9 min of resting ischemia under two conditions: control, which used aortic and carotid baroreflex (ABR and CBR, respectively) deactivation; and suction, which used ABR deactivation alone. The application of neck suction to counteract changes in carotid sinus transmural pressure during cuff release significantly attenuated the MSNA response (which increased 134 +/- 32 U/14 s) compared with control (which increased 195 +/- 43 U/14 s) and caused a greater decrease in MAP (19 +/- 2 vs. 15 +/- 2 mmHg; P < 0.05). Furthermore, during both trials, the HF subjects exhibited a greater decrease in MAP compared with AF subjects despite an augmented baroreflex control of MSNA. These data indicate that the CBR contributes importantly to the MSNA response during acute systemic hypotension. Additionally, we suggest that an impaired control of vascular reactivity hinders blood pressure regulation in HF subjects.

  19. Arterial baroreflex control of sympathetic nerve activity during acute hypotension: effect of fitness.

    PubMed

    Fadel, P J; Stromstad, M; Hansen, J; Sander, M; Horn, K; Ogoh, S; Smith, M L; Secher, N H; Raven, P B

    2001-06-01

    We examined arterial baroreflex control of muscle sympathetic nerve activity (MSNA) during abrupt decreases in mean arterial pressure (MAP) and evaluated whether endurance training alters baroreflex function. Acute hypotension was induced nonpharmacologically in 14 healthy subjects, of which 7 were of high fitness (HF) and 7 were of average fitness (AF), by releasing a unilateral arterial thigh cuff after 9 min of resting ischemia under two conditions: control, which used aortic and carotid baroreflex (ABR and CBR, respectively) deactivation; and suction, which used ABR deactivation alone. The application of neck suction to counteract changes in carotid sinus transmural pressure during cuff release significantly attenuated the MSNA response (which increased 134 +/- 32 U/14 s) compared with control (which increased 195 +/- 43 U/14 s) and caused a greater decrease in MAP (19 +/- 2 vs. 15 +/- 2 mmHg; P < 0.05). Furthermore, during both trials, the HF subjects exhibited a greater decrease in MAP compared with AF subjects despite an augmented baroreflex control of MSNA. These data indicate that the CBR contributes importantly to the MSNA response during acute systemic hypotension. Additionally, we suggest that an impaired control of vascular reactivity hinders blood pressure regulation in HF subjects. PMID:11356607

  20. Differential presynaptic control of the synaptic effectiveness of cutaneous afferents evidenced by effects produced by acute nerve section

    PubMed Central

    Rudomin, P; Jiménez, I; Chávez, D

    2013-01-01

    In the anaesthetized cat, the acute section of the saphenous (Saph) and/or the superficial peroneal (SP) nerves was found to produce a long-lasting increase of the field potentials generated in the dorsal horn by stimulation of the medial branch of the sural (mSU) nerve. This facilitation was associated with changes in the level of the tonic primary afferent depolarization (PAD) of the mSU intraspinal terminals. The mSU afferent fibres projecting into Rexed's laminae III–IV were subjected to a tonic PAD that was reduced by the acute section of the SP and/or the Saph nerves. The mSU afferents projecting deeper into the dorsal horn (Rexed's laminae V–VI) were instead subjected to a tonic PAD that was increased after Saph and SP acute nerve section. A differential control of the synaptic effectiveness of the low-threshold cutaneous afferents according to their sites of termination within the dorsal horn is envisaged as a mechanism that allows selective processing of sensory information in response to tactile and nociceptive stimulation or during the execution of different motor tasks. PMID:23478136

  1. Peripheral nerve blocks for distal extremity surgery.

    PubMed

    Offierski, Chris

    2013-10-01

    Peripheral nerve block is well suited for distal extremity surgery. Blocking the nerves at the distal extremity is easily done. It does not require ultrasound or stimulators to identify the nerve. Blocking nerves in the distal extremity is safe with low risk of toxicity. The effect of the nerve block is limited to the distribution of the nerve. The distal nerves in the lower extremity are sensory branches of the sciatic nerve. This provides a sensory block only. This has the advantage of allowing the patient to actively contract tendons in the foot and ambulate more quickly after surgery. PMID:24093651

  2. Is the Sciatic Functional Index always reliable and reproducible?

    PubMed

    Monte-Raso, Vanessa Vilela; Barbieri, Cláudio Henrique; Mazzer, Nilton; Yamasita, Alexandre Calura; Barbieri, Giuliano

    2008-05-30

    The Sciatic Functional Index (SFI) is a quite useful tool for the evaluation of functional recovery of the sciatic nerve of rats in a number of experimental injuries and treatments. Although it is an objective method, it depends on the examiner's ability to adequately recognize and mark the previously established footprint key points, which is an entirely subjective step, thus potentially interfering with the calculations according to the mathematical formulae proposed by different authors. Thus, an interpersonal evaluation of the reproducibility of an SFI computer-aided method was carried out here to study data variability. A severe crush injury was produced on a 5 mm-long segment of the right sciatic nerve of 20 Wistar rats (a 5000 g load directly applied for 10 min) and the SFI was measured by four different examiners (an experienced one and three newcomers) preoperatively and at weekly intervals from the 1st to the 8th postoperative week. Three measurements were made for each print and the average was calculated and used for statistical analysis. The results showed that interpersonal correlation was high (0.82) in the 3rd, 4th, 5th, 7th and 8th weeks, with an unexpected but significant (p<0.01) drop in the 6th week. There was virtually no interpersonal correlation (correlation index close to 0) on the 1st and 2nd weeks, a period during which the variability between animals and examiners (p=0.24 and 0.32, respectively) was similar, certainly due to a poor definition of the footprints. The authors conclude that the SFI method studied here is only reliable from the 3rd week on after a severe lesion of the sciatic nerve of rats.

  3. Adult skin-derived precursor Schwann cells exhibit superior myelination and regeneration supportive properties compared to chronically denervated nerve-derived Schwann cells.

    PubMed

    Kumar, Ranjan; Sinha, Sarthak; Hagner, Andrew; Stykel, Morgan; Raharjo, Eko; Singh, Karun K; Midha, Rajiv; Biernaskie, Jeff

    2016-04-01

    Functional outcomes following delayed peripheral nerve repair are poor. Schwann cells (SCs) play key roles in supporting axonal regeneration and remyelination following nerve injury, thus understanding the impact of chronic denervation on SC function is critical toward developing therapies to enhance regeneration. To improve our understanding of SC function following acute versus chronic-denervation, we performed functional assays of SCs from adult rodent sciatic nerve with acute- (Day 5 post) or chronic-denervation (Day 56 post), versus embryonic nerves. We also compared Schwann cells derived from adult skin-derived precursors (aSKP-SCs) as an accessible, autologous alternative to supplement the distal (denervated) nerve. We found that acutely-injured SCs and aSKP-SCs exhibited superior proliferative capacity, promotion of neurite outgrowth and myelination of axons, both in vitro and following transplant into a sciatic nerve crush injury model, while chronically-denervated SCs were severely impaired. Acute injury caused re-activation of transcription factors associated with an immature and pro-myelinating SC state (Oct-6, cJun, Sox2, AP2α, cadherin-19), but was diminished with prolonged denervation in vivo and could not be rescued following expansion in vitro suggesting that this is a permanent deficiency. Interestingly, aSKP-SCs closely resembled acutely injured and embryonic SCs, exhibiting elevated expression of these same transcription factors. In summary, prolonged denervation resulted in SC deficiency in several functional parameters that may contribute to impaired regeneration. In contrast, aSKP-SCs closely resemble the regenerative attributes ascribed to acutely-denervated or embryonic SCs emphasizing their potential as an accessible and autologous source of glia cells to enhance nerve regeneration, particularly following delays to surgical repair.

  4. Vasopressin, renin, and cortisol responses to hemorrhage during acute blockade of cardiac nerves in conscious dogs

    NASA Technical Reports Server (NTRS)

    O'Donnell, C. P.; Keil, L. C.; Thrasher, T. N.

    1993-01-01

    The effect of acute cardiac nerve blockade (CNB) on the increases in plasma renin activity (PRA), arginine vasopressin (AVP), and cortisol in response to a 30 ml/kg hemorrhage was determined in conscious dogs (n = 9). Procaine was infused into the pericardial space to produce acute reversible CNB, or saline was infused in the control hemorrhage. Blood was removed from the inferior vena cava at a rate of 1 ml.kg-1.min-1. In the control hemorrhage, plasma AVP increased from 1.8 +/- 0.3 to 219 +/- 66 pg/ml, PRA increased from 0.63 +/- 0.20 to 3.08 +/- 0.91 ng angiotensin I (ANG I).ml-1.3 h-1, and cortisol increased from 1.4 +/- 0.2 to 4.0 +/- 0.7 micrograms/dl. When the hemorrhage was repeated during acute CNB, plasma AVP increased from 2.8 +/- 1.6 to 185 +/- 59 pg/ml, PRA increased from 0.44 +/- 0.14 to 2.24 +/- 0.27 ng ANG I.ml-1.3 h-1, and cortisol increased from 1.9 +/- 0.3 to 5.4 +/- 0.6 micrograms/dl, and none of the increases differed significantly from the responses during the control hemorrhage. Left atrial pressure fell significantly after removal of 6 ml/kg of blood, but mean arterial pressure was maintained at control levels until blood loss reached 20 ml/kg during pericardial infusion of either saline or procaine. The declines in MAP at the 30 ml/kg level of hemorrhage in both treatments were similar. These results demonstrate that acutely blocking input from cardiac receptors does not reduce the increases in plasma AVP, cortisol, and PRA in response to a 30 ml/kg hemorrhage. The results of this study do not support the hypothesis that input from cardiac receptors is required for a normal AVP response to hemorrhage and suggest that other receptors, presumably arterial baroreceptors, can stimulate AVP and cortisol secretion in the absence of signals from the heart.

  5. Muscarinic contribution to the acute cortical effects of vagus nerve stimulation

    NASA Astrophysics Data System (ADS)

    Nichols, Justin A.

    2011-12-01

    Electrical stimulation of the vagus nerve (VNS) has been used to treat more than 60,000 patients with drug-resistant epilepsy and is under investigation as a treatment for several other neurological disorders and conditions. Among these, VNS increases memory performance and enhances recovery of motor and cognitive function in animal models of traumatic brain injury. Recent research indicates that pairing brief VNS with tones multiple-times a day for several weeks induces long-term, input specific cortical plasticity, which can be used to re-normalize the pathological cortical reorganization and eliminate a behavioral correlate of chronic tinnitus in noise exposed rats. Despite the therapeutic potential, the mechanisms of action of VNS remain speculative. In chapter 2 of this dissertation, the acute effects of VNS on cortical synchrony, excitability, and temporal processing are examined. In anesthetized rats implanted with multi-electrode arrays, VNS increased and decorrelated spontaneous multi-unit activity, and suppressed entrainment to repetitive noise burst stimulation at 6 to 8 Hz, but not after systemic administration of the muscarinic antagonist scopolamine. Chapter 3 focuses on VNS-tone pairing induced cortical plasticity. Pairing VNS with a tone one hundred times in anesthetized rats resulted in frequency specific plasticity in 31% of the auditory cortex sites. Half of these sites exhibited a frequency specific increase in firing rate and half exhibited a frequency specific decrease. Muscarinic receptor blockade with scopolamine almost entirely prevented the frequency specific increases, but not decreases. Collectively, these experiments demonstrate the capacity for VNS to not only acutely influence cortical synchrony, and excitability, but to also influence temporal and spectral tuning via muscarinic receptor activation. These results strengthen the hypothesis that acetylcholine and muscarinic receptors are involved in the mechanisms of action of VNS and

  6. Acute pediatric facial nerve paralysis as the first indication for familial cerebral cavernoma: case presentation and literature review.

    PubMed

    Rohani, Pooyan; McRackan, Theodore R; Aulino, Joseph M; Wanna, George B

    2014-01-01

    Familial cerebral cavernoma is an autosomal dominant phenotype with incomplete clinical and neuroimaging penetrance. The most common clinical manifestations include seizures and cerebral hemorrhage. We present the case of a 7-year-old boy who developed acute onset facial nerve paralysis secondary to previously unknown familial cerebral cavernoma. Genetic workup revealed a KRIT1 gene deletion which was later confirmed in the patient's asymptomatic father and younger brother.

  7. Effects of different kinds of acute stress on nerve growth factor content in rat brain.

    PubMed

    von Richthofen, Sita; Lang, Undine E; Hellweg, Rainer

    2003-10-17

    Nerve growth factor (NGF) has several effects on the central nervous system; on the one hand NGF fosters survival and function of cholinergic neurons of the basal forebrain, on the other hand this protein is implicated in the stress response of the hypothalamic-pituitary-adrenocortical axis (HPAA). In this study we tested the influence of threatening and painful stress treatments in three different intensities as well as forced motoric activity on NGF content in different brain areas in adult rats. We found that threatening treatment with or without painful stimuli was followed by a significant decrease of NGF concentration in the amygdala (44.5%; P=0.03) and the frontal cortex (-45.5%; P=0.02). We also observed that after stress of forced motoric activity NGF content in the frontal cortex (-32%; P=0.01) and the hippocampus (-32%; P=0.006) was significantly reduced. Thus, NGF content in distinct brain regions is decreased, following different forms of acute stress. This might be relevant for the pathophysiological understanding of psychiatric diseases, such as depression, which are associated with stress.

  8. Peripheral nerve injuries in athletes. Treatment and prevention.

    PubMed

    Lorei, M P; Hershman, E B

    1993-08-01

    Peripheral nerve lesions are uncommon but serious injuries which may delay or preclude an athlete's safe return to sports. Early, accurate anatomical diagnosis is essential. Nerve lesions may be due to acute injury (e.g. from a direct blow) or chronic injury secondary to repetitive microtrauma (entrapment). Accurate diagnosis is based upon physical examination and a knowledge of the relative anatomy. Palpation, neurological testing and provocative manoeuvres are mainstays of physical diagnosis. Diagnostic suspicion can be confirmed by electrophysiological testing, including electromyography and nerve conduction studies. Proper equipment, technique and conditioning are the keys to prevention. Rest, anti-inflammatories, physical therapy and appropriate splinting are the mainstays of treatment. In the shoulder, spinal accessory nerve injury is caused by a blow to the neck and results in trapezius paralysis with sparing of the sternocleidomastoid muscle. Scapular winging results from paralysis of the serratus anterior because of long thoracic nerve palsy. A lesion of the suprascapular nerve may mimic a rotator cuff tear with pain a weakness of the rotator cuff. Axillary nerve injury often follows anterior shoulder dislocation. In the elbow region, musculocutaneous nerve palsy is seen in weightlifters with weakness of the elbow flexors and dysesthesias of the lateral forearm. Pronator syndrome is a median nerve lesion occurring in the proximal forearm which is diagnosed by several provocative manoeuvres. Posterior interosseous nerve entrapment is common among tennis players and occurs at the Arcade of Froshe--it results in weakness of the wrist and metacarpophalangeal extensors. Ulnar neuritis at the elbow is common amongst baseball pitchers. Carpal tunnel syndrome is a common neuropathy seen in sport and is caused by median nerve compression in the carpal tunnel. Paralysis of the ulnar nerve at the wrist is seen among bicyclists resulting in weakness of grip and

  9. Hereditary neuropathy with liability to pressure palsies presenting with sciatic neuropathy

    PubMed Central

    Topakian, Raffi; Wimmer, Sibylle; Pischinger, Barbara; Pichler, Robert

    2014-01-01

    Hereditary neuropathy with liability to pressure palsies (HNPP) is an autosomal-dominant disorder associated with recurrent mononeuropathies following compression or trivial trauma. Reports on sciatic neuropathy as the presenting manifestation of HNPP are very scarce. We report on a 21-year-old previously healthy man who was admitted with sensorimotor deficits in his left leg. He had no history of preceding transient episodes of weakness or sensory loss. Clinical and electrophysiological examinations were consistent with sciatic neuropathy. Cerebrospinal fluid investigation and MRI of the nerve roots, plexus, and sciatic nerve did not indicate the underlying aetiology. When extended electrophysiological tests revealed multiple subclinical compression neuropathies in the upper limbs, HNPP was contemplated and eventually confirmed by genetic testing. PMID:25326571

  10. Using Eggshell Membrane as Nerve Guide Channels in Peripheral Nerve Regeneration

    PubMed Central

    Farjah, Gholam Hossein; Heshmatian, Behnam; Karimipour, Mojtaba; Saberi, Ali

    2013-01-01

    Objective(s): The aim of this study was to evaluate the final outcome of nerve regeneration across the eggsell membrane (ESM) tube conduit in comparison with autograft. Materials and Methods: Thirty adult male rats (250-300 g) were randomized into (1) ESM conduit, (2) autograft, and (3) sham surgery groups. The eggs submerged in 5% acetic acid. The decalcifying membranes were cut into four pieces, rotated over the teflon mandrel and dried at 37°C. The left sciatic nerve was surgically cut. A 10-mm nerve segment was cut and removed. In the ESM group, the proximal and distal cut ends of the sciatic nerve were telescoped into the nerve guides. In the autograft group, the 10 mm nerve segment was reversed and used as an autologous nerve graft. All animals were evaluated by sciatic functional index (SFI) and electrophysiology testing. Results: The improvement in SFI from the first to the last evalution in ESM and autograft groups were evaluated. On days 49 and 60 post-operation, the mean SFI of ESM group was significantly greater than the autograft group (P< 0.05). On day 90, the mean nerve conduction velocity (NCV) of ESM group was greater than autograft group, although the difference was not statistically significant (P> 0.05). Conclusion: These findings demonstrate that ESM effectively enhances nerve regeneration and promotes functional recovery in injured sciatic nerve of rat. PMID:24106593

  11. Nerve growth factor receptor gene is at human chromosome region 17q12-17q22, distal to the chromosome 17 breakpoint in acute leukemias

    SciTech Connect

    Huebner, K.; Isobe, M.; Chao, M.; Bothwell, M.; Ross, A.H.; Finan, J.; Hoxie, J.A.; Sehgal, A.; Buck, C.R.; Lanahan, A.

    1986-03-01

    Genomic and cDNA clones for the human nerve growth factor receptor have been used in conjunction with somatic cell hybrid analysis and in situ hybridization to localize the nerve growth factor receptor locus to human chromosome region 17q12-q22. Additionally, part, if not all, of the nerve growth factor receptor locus is present on the translocated portion of 17q (17q21-qter) from a poorly differential acute leukemia in which the chromosome 17 breakpoint was indistinguishable cytogenetically from the 17 breakpoint observed in the t(15;17)(q22;q21) translocation associated with acute promyelocytic leukemia. Thus the nerve growth factor receptor locus may be closely distal to the acute promyelocytic leukemia-associated chromosome 17 breakpoint at 17q21.

  12. The effect of aging on the density of the sensory nerve fiber innervation of bone and acute skeletal pain

    PubMed Central

    Jimenez-Andrade, Juan M.; Mantyh, William G.; Bloom, Aaron P.; Freeman, Katie T.; Ghilardi, Joseph R.; Kuskowski, Michael A.; Mantyh, Patrick W.

    2010-01-01

    As humans age there is a decline in most sensory systems including vision, hearing, taste, smell, and tactile acuity. In contrast, the frequency and severity of musculoskeletal pain generally increases with age. To determine whether the density of sensory nerve fibers that transduce skeletal pain changes with age, calcitonin gene related peptide (CGRP) and neurofilament 200 kDa (NF200) sensory nerve fibers that innervate the femur were examined in the femurs of young (4 month old), middle-aged (13 month) and old (36 month) male F344/BNF1 rats. Whereas the bone quality showed a significant age-related decline, the density of CGRP+ and NF200+ nerve fibers that innervate the bone remained remarkably unchanged as well as the severity of acute skeletal fracture pain. Thus, while bone mass, quality and strength undergo a significant decline with age, the density of sensory nerve fibers that transduce noxious stimuli remain largely intact. These data may in part explain why musculoskeletal pain increases with age. PMID:20947214

  13. Effects of subacute pretreatment with carbamate together with acute adjunct pretreatment against nerve agent exposure. (Reannouncement with new availability information)

    SciTech Connect

    Anderson, D.R.; Harris, L.W.; Lennox, W.J.; Solana, R.P.

    1991-12-31

    Acute carbamate pretreatment, in conjunction with atropine pretreatment or followed by atropine and oxime therapy has been shown to protect rabbits, rats, guinea pigs and monkeys against multiple lethal doses of soman. In those experiments, pretreated animals were usually challenged with soman at the time of peak whole blood acetylcholinesterase (AChE) inhibition by the carbamate or when the concentration of carbamate in the blood was expected to be rapidly diminishing. However, soldiers in a chemical environment, having taken carbamate orally might well be exposed to nerve agent shortly thereafter. Thus, both active carbamate and nerve agent would be entering the blood simultaneously. In a recent study it was reported that subacute administration of physostigmine (Phy), via subcutaneously implanted 28 day osmotic minipump, afforded protection against an iv challenge of soman on the 27th day.

  14. Fibrolipomatous hamartoma of the median nerve: A cause of acute bilateral carpal tunnel syndrome in a three-year-old child: A case report and comprehensive literature review

    PubMed Central

    Senger, Jenna-Lynn; Classen, Dale; Bruce, Garth; Kanthan, Rani

    2014-01-01

    A three-year-old boy was investigated for inexplicable incessant crying. On examination, his left wrist was mildly swollen (three to four months) and sensitive. Exploration and carpal tunnel decompression of the left wrist with incisional biopsy was performed for the presence of a fusiform swelling intimately associated with the median nerve. Histopathology revealed the presence of enlarged nerve bundles admixed with mature fat cells and diffuse fibroblastic proliferation. Three months later, he underwent urgent contralateral carpal tunnel decompression for a similar presentation. The final diagnosis was bilateral fibrolipomatous hamartoma (FLH) of the median nerves causing acute bilateral compression neuropathy. FLH of the median nerve is an extremely unusual cause of acute bilateral carpal tunnel syndrome in a young child presenting with ‘incessant crying’. A comprehensive review of FLH including epidemiology, etiology, clinical presentation, differential diagnosis, imaging, pathology, treatment and prognosis is discussed. PMID:25332651

  15. Expression of nerve growth factor is upregulated in the rat thymic epithelial cells during thymus regeneration following acute thymic involution.

    PubMed

    Lee, Hee-Woo; Kim, Sung-Min; Shim, Na-Ri; Bae, Soo-Kyung; Jung, Il-Gun; Kwak, Jong-Young; Kim, Bong-Seon; Kim, Jae-Bong; Moon, Jeon-Ok; Chung, Joo-Seop; Yoon, Sik

    2007-06-01

    Neuroimmune networks in the thymic microenvironment are thought to be involved in the regulation of T cell development. Nerve growth factor (NGF) is increasingly recognized as a potent immunomodulator, promoting "cross-talk" between various types of immune system cells. The present study describes the expression of NGF during thymus regeneration following acute involution induced by cyclophosphamide in the rat. Immunohistochemical stain demonstrated not only the presence of NGF but also its upregulated expression mainly in the subcapsular, paraseptal, and perivascular epithelial cells, and medullary epithelial cells including Hassall's corpuscles in both the normal and regenerating thymus. Biochemical data obtained using Western blot and RT-PCR supported these results and showed that thymic extracts contain NGF protein and mRNA, at higher levels during thymus regeneration. Thus, our results suggest that NGF expressed in these thymic epithelial cells plays a role in the T lymphopoiesis associated with thymus regeneration during recovery from acute thymic involution.

  16. Workup and Management of Persistent Neuralgia following Nerve Block

    PubMed Central

    Weyker, Paul David; Webb, Christopher Allen-John; Pham, Thoha M.

    2016-01-01

    Neurological injuries following peripheral nerve blocks are a relatively rare yet potentially devastating complication depending on the type of lesion, affected extremity, and duration of symptoms. Medical management continues to be the treatment modality of choice with multimodal nonopioid analgesics as the cornerstone of this therapy. We report the case of a 28-year-old man who developed a clinical common peroneal and lateral sural cutaneous neuropathy following an uncomplicated popliteal sciatic nerve block. Workup with electrodiagnostic studies and magnetic resonance neurography revealed injury to both the femoral and sciatic nerves. Diagnostic studies and potential mechanisms for nerve injury are discussed. PMID:26904304

  17. Temporal Analysis of Gene Expression in the Murine Schwann Cell Lineage and the Acutely Injured Postnatal Nerve

    PubMed Central

    Touahri, Yacine; Stratton, Jo Anne; Biernaskie, Jeff; Schuurmans, Carol

    2016-01-01

    Schwann cells (SCs) arise from neural crest cells (NCCs) that first give rise to SC precursors (SCPs), followed by immature SCs, pro-myelinating SCs, and finally, non-myelinating or myelinating SCs. After nerve injury, mature SCs ‘de-differentiate’, downregulating their myelination program while transiently re-activating early glial lineage genes. To better understand molecular parallels between developing and de-differentiated SCs, we characterized the expression profiles of a panel of 12 transcription factors from the onset of NCC migration through postnatal stages, as well as after acute nerve injury. Using Sox10 as a pan-glial marker in co-expression studies, the earliest transcription factors expressed in E9.0 Sox10+ NCCs were Sox9, Pax3, AP2α and Nfatc4. E10.5 Sox10+ NCCs coalescing in the dorsal root ganglia differed slightly, expressing Sox9, Pax3, AP2α and Etv5. E12.5 SCPs continued to express Sox10, Sox9, AP2α and Pax3, as well as initiating Sox2 and Egr1 expression. E14.5 immature SCs were similar to SCPs, except that they lost Pax3 expression. By E18.5, AP2α, Sox2 and Egr1 expression was turned off in the nerve, while Jun, Oct6 and Yy1 expression was initiated in pro-myelinating Sox9+/Sox10+ SCs. Early postnatal and adult SCs continued to express Sox9, Jun, Oct6 and Yy1 and initiated Nfatc4 and Egr2 expression. Notably, at all stages, expression of each marker was observed only in a subset of Sox10+ SCs, highlighting the heterogeneity of the SC pool. Following acute nerve injury, Egr1, Jun, Oct6, and Sox2 expression was upregulated, Egr2 expression was downregulated, while Sox9, Yy1, and Nfatc4 expression was maintained at similar frequencies. Notably, de-differentiated SCs in the injured nerve did not display a transcription factor profile corresponding to a specific stage in the SC lineage. Taken together, we demonstrate that uninjured and injured SCs are heterogeneous and distinct from one another, and de-differentiation recapitulates

  18. Temporal Analysis of Gene Expression in the Murine Schwann Cell Lineage and the Acutely Injured Postnatal Nerve.

    PubMed

    Balakrishnan, Anjali; Stykel, Morgan G; Touahri, Yacine; Stratton, Jo Anne; Biernaskie, Jeff; Schuurmans, Carol

    2016-01-01

    Schwann cells (SCs) arise from neural crest cells (NCCs) that first give rise to SC precursors (SCPs), followed by immature SCs, pro-myelinating SCs, and finally, non-myelinating or myelinating SCs. After nerve injury, mature SCs 'de-differentiate', downregulating their myelination program while transiently re-activating early glial lineage genes. To better understand molecular parallels between developing and de-differentiated SCs, we characterized the expression profiles of a panel of 12 transcription factors from the onset of NCC migration through postnatal stages, as well as after acute nerve injury. Using Sox10 as a pan-glial marker in co-expression studies, the earliest transcription factors expressed in E9.0 Sox10+ NCCs were Sox9, Pax3, AP2α and Nfatc4. E10.5 Sox10+ NCCs coalescing in the dorsal root ganglia differed slightly, expressing Sox9, Pax3, AP2α and Etv5. E12.5 SCPs continued to express Sox10, Sox9, AP2α and Pax3, as well as initiating Sox2 and Egr1 expression. E14.5 immature SCs were similar to SCPs, except that they lost Pax3 expression. By E18.5, AP2α, Sox2 and Egr1 expression was turned off in the nerve, while Jun, Oct6 and Yy1 expression was initiated in pro-myelinating Sox9+/Sox10+ SCs. Early postnatal and adult SCs continued to express Sox9, Jun, Oct6 and Yy1 and initiated Nfatc4 and Egr2 expression. Notably, at all stages, expression of each marker was observed only in a subset of Sox10+ SCs, highlighting the heterogeneity of the SC pool. Following acute nerve injury, Egr1, Jun, Oct6, and Sox2 expression was upregulated, Egr2 expression was downregulated, while Sox9, Yy1, and Nfatc4 expression was maintained at similar frequencies. Notably, de-differentiated SCs in the injured nerve did not display a transcription factor profile corresponding to a specific stage in the SC lineage. Taken together, we demonstrate that uninjured and injured SCs are heterogeneous and distinct from one another, and de-differentiation recapitulates

  19. Exogenous Neuritin Promotes Nerve Regeneration After Acute Spinal Cord Injury in Rats.

    PubMed

    Gao, Rui; Li, Xingyi; Xi, Shaosong; Wang, Haiyan; Zhang, Hong; Zhu, Jingling; Shan, Liya; Song, Xiaoming; Luo, Xing; Yang, Lei; Huang, Jin

    2016-07-01

    Insufficient local levels of neurotrophic factor after spinal cord injury (SCI) are the leading cause of secondary injury and limited axonal regeneration. Neuritin belongs to a family of neurotrophic factors that promote neurite outgrowth, maintain neuronal survival, and provide a favorable microenvironment for the regeneration and repair of nerve cells after injury. However, it is not known whether the exogenously applied neuritin protein has a positive effect on nerve repair after SCI. This was investigated in the present study using purified human recombinant neuritin expressed in and purified from Pichia pastoris, which was tested in a rat SCI model. A recombinant neuritin concentration of 60 μg/ml induced the recovery of hind limb motor function and stimulated nerve regeneration in rats with SCI. Continuous administration of neuritin at this dose at an early stage after SCI inhibited poly ADP ribose polymerase (PARP) protein degradation and decreased neuronal apoptosis. In addition, during the critical postinjury period of axonal regeneration, exogenous neuritin treatment increased the expression of neurofilament 200 and growth-associated protein 43 in the damaged tissue, which was associated with the restoration of hind limb movement. These results suggest that neuritin creates an environment that promotes nerve cell survival and neurite regeneration after SCI, which contribute to nerve regeneration and the recovery of motor function. PMID:27009445

  20. Arthroscopic medial meniscus trimming or repair under nerve blocks: Which nerves should be blocked?

    PubMed Central

    Taha, AM; Abd-Elmaksoud, AM

    2016-01-01

    Background: This study aimed to determine the role of the sciatic and obturator nerve blocks (in addition to femoral block) in providing painless arthroscopic medial meniscus trimming/repair. Materials and Methods: One hundred and twenty patients with medial meniscus tear, who had been scheduled to knee arthroscopy, were planned to be included in this controlled prospective double-blind study. The patients were randomly allocated into three equal groups; FSO, FS, and FO. The femoral, sciatic, and obturator nerves were blocked in FSO groups. The femoral and sciatic nerves were blocked in FS group, while the femoral and obturator nerves were blocked in FO group. Intraoperative pain and its causative surgical maneuver were recorded. Results: All the patients (n = 7, 100%) in FO group had intraoperative pain. The research was terminated in this group but completed in FS and FSO groups (40 patients each). During valgus positioning of the knee for surgical management of the medial meniscus tear, the patients in FS group experienced pain more frequently than those in FSO group (P = 0.005). Conclusion: Adding a sciatic nerve block to the femoral nerve block is important for painless knee arthroscopy. Further adding of an obturator nerve block may be needed when a valgus knee position is required to manage the medial meniscus tear. PMID:27375382

  1. Acellular Nerve Allografts in Peripheral Nerve Regeneration: A Comparative Study

    PubMed Central

    Moore, Amy M.; MacEwan, Matthew; Santosa, Katherine B.; Chenard, Kristofer E.; Ray, Wilson Z.; Hunter, Daniel A.; Mackinnon, Susan E.; Johnson, Philip J.

    2011-01-01

    Background Processed nerve allografts offer a promising alternative to nerve autografts in the surgical management of peripheral nerve injuries where short deficits exist. Methods Three established models of acellular nerve allograft (cold-preserved, detergent-processed, and AxoGen® -processed nerve allografts) were compared to nerve isografts and silicone nerve guidance conduits in a 14 mm rat sciatic nerve defect. Results All acellular nerve grafts were superior to silicone nerve conduits in support of nerve regeneration. Detergent-processed allografts were similar to isografts at 6 weeks post-operatively, while AxoGen®-processed and cold-preserved allografts supported significantly fewer regenerating nerve fibers. Measurement of muscle force confirmed that detergent-processed allografts promoted isograft-equivalent levels of motor recovery 16 weeks post-operatively. All acellular allografts promoted greater amounts of motor recovery compared to silicone conduits. Conclusions These findings provide evidence that differential processing for removal of cellular constituents in preparing acellular nerve allografts affects recovery in vivo. PMID:21660979

  2. Promoting peripheral nerve regeneration with biodegradable poly (DL-lactic acid) films

    PubMed Central

    Li, Ruijun; Chen, Lei; Fu, Jinling; Liu, Zhigang; Wang, Shuang; Pan, Yuehai

    2015-01-01

    Regeneration and repair of peripheral nerve injury has always been a major problem in the clinic. The conventional technique based on suturing the nerve ends to each other coupled with the implantation of nerve conduits outside is associated with postoperative adhesions and scar problems. Recently, a novel biodegradable poly (DL-lactic acid) (PDLLA) film has been introduced. This novel anti-adhesion film has a porous structure with better mechanical properties, better flexibility, and more controllable degradation as compared to traditional non-porous nerve conduits. However, little is known about the effects of such PDLLA films on regeneration and repair of peripheral nerve injury in vivo. In this study, we evaluated the effects of PDLLA films implantation after sciatic nerve transection and anastomosis on subsequent sciatic nerve regeneration in vivo, using a rat sciatic nerve injury model. Sciatic nerve transection surgery coupled with direct suturing only, suturing and wrapping with traditional nerve conduits, or suturing and wrapping with PDLLA films was performed on adult Wistar rats. The additional wrapping with PDLLA films inhibited the nerve adhesion after 12 weeks recovery from surgery. It also increased the compound muscle action potentials and tibialis and gastrocnemius muscle wet weight ratio following 8 weeks recovery from surgery. Regenerated nerve fibers were relatively straight and the aligned structure was complete in rats with implantations of PDLLA films. The results suggested that PDLLA films can improve the nutritional status in the muscles innervated by the damaged nerves and promote nerve regeneration in vivo. PMID:26339372

  3. Successful Reconstruction of Nerve Defects Using Distraction Neurogenesis with a New Experimental Device

    PubMed Central

    Yousef, Mohamed Abdelhamid Ali; Dionigi, Paolo; Marconi, Stefania; Calligaro, Alberto; Cornaglia, Antonia Icaro; Alfonsi, Enrico; Auricchio, Ferdinando

    2015-01-01

    Introduction: Repair of peripheral nerve injuries is an intensive area of challenge and research in modern reconstructive microsurgery. Intensive research is being carried out to develop effective alternatives to the standard nerve autografting, avoiding its drawbacks. The aim of the study was to evaluate the effectiveness of a newly designed mechanical device for the reconstruction of the sciatic nerve in rats in comparison to nerve autografting and to assess the pain during the period of distraction neurogenesis. Methods: Fourteen Sprague Dawley rats were used and randomly assigned into 2 groups with 7 rats in each group; group A (Nerve Autografting group) in which a 10-mm segment of the sciatic nerve was resected and rotated 180 degrees, then primary end-to-end neurorrhaphy was performed in the reverse direction; group B (Nerve Lengthening group) in which the mechanical device was inserted after surgical resection of 10 mm of the sciatic nerve, then secondary end-to-end neurorrhaphy was performed after completing the nerve lengthening. Thirteen weeks later, assessment of the functional sciatic nerve recovery using static sciatic index (SSI) was performed. Furthermore, fourteen weeks after the nerve resection, assessment of the nerve regeneration with electrophysiological study and histological analysis were performed. Also, gastrocnemius wet weight was measured. For pain assessment in group B, Rat Grimace Scale (RGS) score was used. Results: Significantly better functional recovery rate (using the SSI) was reported in the nerve lengthening group in comparison to autografting group. Also, a statistically significant higher nerve conduction velocity was detected in the nerve lengthening group. On histological analysis of the distal nerve section at 3 mm distal to the nerve repair site, significant myelin sheath thickness was detected in the nerve lengthening group. Discussion: Distraction neurogenesis with the new experimental device is a reliable therapeutic

  4. Isolated acute sphenoid sinusitis presenting with hemicranial headache and ipsilateral abducens nerve palsy.

    PubMed

    Gupta, Rahul; Shukla, Rakesh; Mishra, Anupam; Parihar, Anit

    2015-06-08

    Isolated sphenoid sinusitis is a rare disorder and may present with complications due to its anatomical location and proximity to the intracranial and orbital contents. It is frequently misdiagnosed, because the sphenoid sinus is not visualised adequately with routine sinus radiographs and is not accessible to direct clinical examination. We report a case who presented with hemicranial headache and ipsilateral abducens nerve palsy as the presenting feature of sphenoid sinusitis. The symptoms disappeared within a week of conservative treatment. Sphenoid sinusitis should be kept in the differential diagnosis of isolated sixth cranial nerve palsy, especially in the presence of headache, and all patients should be investigated with CT/MRI brain. Prompt diagnosis and management before intracranial extension can prevent devastating complications.

  5. High sensitivity recording of afferent nerve activity using ultra-compliant microchannel electrodes: an acute in vivo validation

    NASA Astrophysics Data System (ADS)

    Minev, Ivan R.; Chew, Daniel J.; Delivopoulos, Evangelos; Fawcett, James W.; Lacour, Stéphanie P.

    2012-04-01

    Neuroprostheses interfaced with transected peripheral nerves are technological routes to control robotic limbs as well as convey sensory feedback to patients suffering from traumatic neural injuries or degenerative diseases. To maximize the wealth of data obtained in recordings, interfacing devices are required to have intrafascicular resolution and provide high signal-to-noise ratio (SNR) recordings. In this paper, we focus on a possible building block of a three-dimensional regenerative implant: a polydimethylsiloxane (PDMS) microchannel electrode capable of highly sensitive recordings in vivo. The PDMS 'micro-cuff' consists of a 3.5 mm long (100 µm × 70 µm cross section) microfluidic channel equipped with five evaporated Ti/Au/Ti electrodes of sub-100 nm thickness. Individual electrodes have average impedance of 640 ± 30 kΩ with a phase angle of -58 ± 1 degrees at 1 kHz and survive demanding mechanical handling such as twisting and bending. In proof-of-principle acute implantation experiments in rats, surgically teased afferent nerve strands from the L5 dorsal root were threaded through the microchannel. Tactile stimulation of the skin was reliably monitored with the three inner electrodes in the device, simultaneously recording signal amplitudes of up to 50 µV under saline immersion. The overall SNR was approximately 4. A small but consistent time lag between the signals arriving at the three electrodes was observed and yields a fibre conduction velocity of 30 m s-1. The fidelity of the recordings was verified by placing the same nerve strand in oil and recording activity with hook electrodes. Our results show that PDMS microchannel electrodes open a promising technological path to 3D regenerative interfaces.

  6. A method for evaluating the selectivity of electrodes implanted for nerve simulation.

    PubMed

    Liang, D H; Kovacs, G T; Storment, C W; White, R L

    1991-05-01

    The scale of stimulating electrodes possible for use in functional electrical stimulation to restore motor and sensory function is rapidly approaching that of individual neurons. Although the electrodes may approach the dimensions of single nerve cells, it is unclear if the region of excitation elicited by each electrode will be correspondingly small. Previous techniques for evaluating this have either been tedious or have lacked the resolution necessary. This paper describes a method that uses the refractory interaction of the compound action potentials elicited by a stimulus pulse pair, along with high-resolution recording of those potentials, to achieve measurements of the selectivity of stimulation down to the scale of a few axon diameters. The feasibility of this technique is demonstrated in sciatic nerves of frogs (Rana Catesbiana) acutely implanted with a sapphire electrode array. PMID:1874526

  7. [Pyrimidal syndrome and anatomical variations as a cause of insidious sciatic pain].

    PubMed

    Ortiz Sánchez, V E; Charco Roca, L M; Soria Quiles, A; Zafrilla Disla, E; Hernandez Mira, F

    2014-11-01

    The case is presented of a 42 year old woman who had been suffering a loss of strength in her left leg for six years. After an extensive diagnostic study, the pain was classified as of functional origin by a diagnosis of exclusion. Since then, the patient has tried all kind of drug treatments and conservative techniques without improvement. After an exhaustive study with inconclusive results, the case was discussed with the Orthopaedics Department, who performed an exploratory surgery, in which compression of the sciatic nerve due to an anatomical variation of the piriformis muscle was observed. Part of the muscle was resected during surgery and the sciatic nerve was freed, after which the patient experienced a great improvement.

  8. Effect of acute and chronic administration of L-tyrosine on nerve growth factor levels in rat brain.

    PubMed

    Ferreira, Gabriela K; Jeremias, Isabela C; Scaini, Giselli; Carvalho-Silva, Milena; Gomes, Lara M; Furlanetto, Camila B; Morais, Meline O; Schuck, Patrícia F; Ferreira, Gustavo C; Streck, Emilio L

    2013-08-01

    Most inborn errors of tyrosine catabolism produce hypertyrosinemia. Neurological manifestations are variable and some patients are developmentally normal, while others show different degrees of developmental retardation. Considering that current data do not eliminate the possibility that elevated levels of tyrosine and/or its derivatives may have noxious effects on central nervous system development in some patients, the present study evaluated nerve growth factor (NGF) levels in hippocampus, striatum and posterior cortex of young rats. In our acute protocol, Wistar rats (10 and 30 days old) were killed 1 h after a single intraperitoneal administration of L-tyrosine (500 mg/kg) or saline. Chronic administration consisted of L-tyrosine (500 mg/kg) or saline injections 12 h apart for 24 days in Wistar rats (7 days old); the rats were killed 12 h after the last injection. NGF levels were then evaluated. Our findings showed that acute administration of L-tyrosine decreased NGF levels in striatum of 10-day-old rats. In the 30-day-old rats, NGF levels were decreased in hippocampus and posterior cortex. On the other hand, chronic administration of L-tyrosine increased NGF levels in posterior cortex. Decreased NGF may impair growth, differentiation, survival and maintenance of neurons. PMID:23690230

  9. HINDBRAIN AND CRANIAL NERVE DYSMORPHOGENESIS RESULT FROM ACUTE MATERNAL ETHANOL ADMINISTRATION

    EPA Science Inventory

    Acute exposure of mouse embryos to ethanol during stages of hindbrain segmentation results in excessive cell death in specific cell populations. This study details the ethanol-induced cell loss and defines the subsequent effects of this early insult on rhombomere and cranial ner...

  10. Acute and chronic administration of the branched-chain amino acids decreases nerve growth factor in rat hippocampus.

    PubMed

    Scaini, Giselli; Mello-Santos, Lis Mairá; Furlanetto, Camila B; Jeremias, Isabela C; Mina, Francielle; Schuck, Patrícia F; Ferreira, Gustavo C; Kist, Luiza W; Pereira, Talita C B; Bogo, Maurício R; Streck, Emilio L

    2013-12-01

    Maple syrup urine disease (MSUD) is a neurometabolic disorder caused by deficiency of the activity of the mitochondrial enzyme complex branched-chain α-keto acid dehydrogenase leading to accumulation of the branched-chain amino acids (BCAA) and their corresponding branched-chain α-keto acids. In this study, we examined the effects of acute and chronic administration of BCAA on protein levels and mRNA expression of nerve growth factor (NGF) considering that patients with MSUD present neurological dysfunction and cognitive impairment. Considering previous observations, it is suggested that oxidative stress may be involved in the pathophysiology of the neurological dysfunction of MSUD. We also investigated the influence of antioxidant treatment (N-acetylcysteine and deferoxamine) in order to verify the influence of oxidative stress in the modulation of NGF levels. Our results demonstrated decreased protein levels of NGF in the hippocampus after acute and chronic administration of BCAA. In addition, we showed a significant decrease in the expression of ngf in the hippocampus only following acute administration in 10-day-old rats. Interestingly, antioxidant treatment was able to prevent the decrease in NGF levels by increasing ngf expression. In conclusion, the results suggest that BCAA is involved in the regulation of NGF in the developing rat. Thus, it is possible that alteration of neurotrophin levels during brain maturation could be of pivotal importance in the impairment of cognition provoked by BCAA. Moreover, the decrease in NGF levels was prevented by antioxidant treatment, reinforcing that the hypothesis of oxidative stress can be an important pathophysiological mechanism underlying the brain damage observed in MSUD. PMID:23559405

  11. Collagen synthesis in axotomized peripheral nerve: evidence against Schwann cell involvement.

    PubMed

    Eather, T F; Pollock, M

    1987-04-01

    To explore the role of Schwann cells in nerve collagen formation, fascicular collagen was measured in axotomized rat sciatic nerve after regeneration or permanent axotomy. The same increase in fascicular collagen was seen in both paradigms. Thus there is no evidence that Schwann cells unassociated with axons make an important contribution to nerve collagen synthesis after transection.

  12. Complement components of nerve regeneration conditioned fluid influence the microenvironment of nerve regeneration

    PubMed Central

    Li, Guang-shuai; Li, Qing-feng; Dong, Ming-min; Zan, Tao; Ding, Shuang; Liu, Lin-bo

    2016-01-01

    Nerve regeneration conditioned fluid is secreted by nerve stumps inside a nerve regeneration chamber. A better understanding of the proteinogram of nerve regeneration conditioned fluid can provide evidence for studying the role of the microenvironment in peripheral nerve regeneration. In this study, we used cylindrical silicone tubes as the nerve regeneration chamber model for the repair of injured rat sciatic nerve. Isobaric tags for relative and absolute quantitation proteomics technology and western blot analysis confirmed that there were more than 10 complement components (complement factor I, C1q-A, C1q-B, C2, C3, C4, C5, C7, C8β and complement factor D) in the nerve regeneration conditioned fluid and each varied at different time points. These findings suggest that all these complement components have a functional role in nerve regeneration. PMID:27212935

  13. Acute VI nerve palsy in a 4 year-old girl with Chiari I malformation and pontomedullary extension of syringomyelia: case report and review of the literature.

    PubMed

    Massey, Shavonne L; Buland, Justin; Hauber, Stacey; Piatt, Joseph; Goraya, Jatinder; Faerber, Eric; Valencia, Ignacio

    2011-07-01

    We report the case of a previously healthy 4 year-old African American female who presented to the emergency department with acute onset of unilateral abducens nerve palsy and torticollis. Within 12 h of presentation, the patient's symptoms progressed to include ipsilateral facial nerve palsy and gait ataxia. On exam, the patient demonstrated right cranial nerve VI and VII palsies, ataxic gait with left lateropulsion, spasticity of bilateral lower extremities with clonus, and the presence of bilateral Babinski sign. MRI of the brain and spinal cord revealed severe Chiari I malformation with associated extensive holochord syringomyelia and syringobulbia. The patient underwent successful surgical decompression 72 h after initial presentation. We review the literature on Chiari malformations and syringomyelia, including epidemiology, presentation and neurological manifestations, and treatment recommendations. As our patient had a very acute presentation, we additionally review the previously reported cases of acute and atypical presentation of patients with Chiari I malformation and syringomyelia. The aim of this report is to make practitioners aware of the acuteness with which children with Chiari malformation type I with syringomyelia and syringobulbia can present.

  14. Acute cyclooxygenase inhibition does not alter muscle sympathetic nerve activity or forearm vasodilator responsiveness in lean and obese adults

    PubMed Central

    Barnes, Jill N.; Charkoudian, Nisha; Matzek, Luke J.; Johnson, Christopher P.; Joyner, Michael J.; Curry, Timothy B.

    2014-01-01

    Abstract Obesity is often characterized by chronic inflammation that may contribute to increased cardiovascular risk via sympathoexcitation and decreased vasodilator responsiveness. We hypothesized that obese individuals would have greater indices of inflammation compared with lean controls, and that cyclooxygenase inhibition using ibuprofen would reduce muscle sympathetic nerve activity (MSNA) and increase forearm blood flow in these subjects. We measured MSNA, inflammatory biomarkers (C‐reactive protein [CRP] and Interleukin‐6 [IL‐6]), and forearm vasodilator responses to brachial artery acetylcholine and sodium nitroprusside in 13 men and women (7 lean; 6 obese) on two separate study days: control (CON) and after 800 mg ibuprofen (IBU). CRP (1.7 ± 0.4 vs. 0.6 ± 0.3 mg/L; P < 0.05) and IL‐6 (4.1 ± 1.5 vs. 1.0 ± 0.1pg/mL; P < 0.05) were higher in the obese group during CON and tended to decrease with IBU (IL‐6: P < 0.05; CRP: P = 0.14). MSNA was not different between groups during CON (26 ± 4 bursts/100 heart beats (lean) versus 26 ± 4 bursts/100 heart beats (obese); P = 0.50) or IBU (25 ± 4 bursts/100 heart beats (lean) versus 30 ± 5 bursts/100 heart beats (obese); P = 0.25), and was not altered by IBU. Forearm vasodilator responses were unaffected by IBU in both groups. In summary, an acute dose of ibuprofen did not alter sympathetic nerve activity or forearm blood flow responses in healthy obese individuals, suggesting that the cyclooxygenase pathway is not a major contributor to these variables in this group. PMID:25347862

  15. Essential fatty acids prevent slowed nerve conduction in streptozotocin diabetic rats.

    PubMed

    Julu, P O

    1988-01-01

    Rats were given streptozotocin to induce insulin-dependent diabetes or citrate buffer alone in two experiments. Initially, the effect of 5 wks of dietary gamma-linolenic acid (GLA) plus eicosapentaenoic acid (EPA) on cutaneous nerve conduction velocity (CV) was examined. CV was determined by direct stimulation and recording from saphenous nerve under urethane anesthesia. Secondly, a 5 weeks study of supplementing the diet with GLA, GLA and EPA, or hydrogenated coconut oil (HC) was done. In addition, motor nerve CV was determined by directly stimulating sciatic nerve and recording from gastrocnemius muscle. The acute diabetes led to weight loss, and elevated blood glucose and glycosylated hemoglobin levels. Essential fatty acid (EFA) supplementation had no effect on any of these measures of severity of diabetes. In diabetic rats without EFA supplementation, CV of the myelinated fibers fell by 19-21%, while those receiving both GLA and EPA had normal CV. In diabetic rats receiving GLA alone, CV fell by 5-7%, which was significantly less than those without EFA supplementation (p less than 0.01 for cutaneous, and p less than 0.001 for motor nerves).

  16. NRF2 promotes neuronal survival in neurodegeneration and acute nerve damage

    PubMed Central

    Xiong, Wenjun; MacColl Garfinkel, Alexandra E.; Li, Yiqing; Benowitz, Larry I.; Cepko, Constance L.

    2015-01-01

    Oxidative stress contributes to the loss of neurons in many disease conditions as well as during normal aging; however, small-molecule agents that reduce oxidation have not been successful in preventing neurodegeneration. Moreover, even if an efficacious systemic reduction of reactive oxygen and/or nitrogen species (ROS/NOS) could be achieved, detrimental side effects are likely, as these molecules regulate normal physiological processes. A more effective and targeted approach might be to augment the endogenous antioxidant defense mechanism only in the cells that suffer from oxidation. Here, we created several adeno-associated virus (AAV) vectors to deliver genes that combat oxidation. These vectors encode the transcription factors NRF2 and/or PGC1a, which regulate hundreds of genes that combat oxidation and other forms of stress, or enzymes such as superoxide dismutase 2 (SOD2) and catalase, which directly detoxify ROS. We tested the effectiveness of this approach in 3 models of photoreceptor degeneration and in a nerve crush model. AAV-mediated delivery of NRF2 was more effective than SOD2 and catalase, while expression of PGC1a accelerated photoreceptor death. Since the NRF2-mediated neuroprotective effects extended to photoreceptors and retinal ganglion cells, which are 2 very different types of neurons, these results suggest that this targeted approach may be broadly applicable to many diseases in which cells suffer from oxidative damage. PMID:25798616

  17. Comparison of acute non-visual bright light responses in patients with optic nerve disease, glaucoma and healthy controls.

    PubMed

    Münch, M; Léon, L; Collomb, S; Kawasaki, A

    2015-01-01

    This study examined the effect of optic nerve disease, hence retinal ganglion cell loss, on non-visual functions related to melanopsin signalling. Test subjects were patients with bilateral visual loss and optic atrophy from either hereditary optic neuropathy (n = 11) or glaucoma (n = 11). We measured melatonin suppression, subjective sleepiness and cognitive functions in response to bright light exposure in the evening. We also quantified the post-illumination pupil response to a blue light stimulus. All results were compared to age-matched controls (n = 22). Both groups of patients showed similar melatonin suppression when compared to their controls. Greater melatonin suppression was intra-individually correlated to larger post-illumination pupil response in patients and controls. Only the glaucoma patients demonstrated a relative attenuation of their pupil response. In addition, they were sleepier with slower reaction times during nocturnal light exposure. In conclusion, glaucomatous, but not hereditary, optic neuropathy is associated with reduced acute light effects. At mild to moderate stages of disease, this is detected only in the pupil function and not in responses conveyed via the retinohypothalamic tract such as melatonin suppression. PMID:26478261

  18. Nerve growth factor acutely reduces chemical transmission by means of postsynaptic TrkA-like receptors in squid giant synapse

    PubMed Central

    Moreno, Herman; Nadal, Marcela; Leznik, Elena; Sugimori, Mutsuyuki; Lax, Irit; Schlessinger, Joseph; Llinás, Rodolfo

    1998-01-01

    Tyrosine phosphorylation has been shown to be an important modulator of synaptic transmission in both vertebrates and invertebrates. Such findings hint toward the existence of extracellular ligands capable of activating this widely represented signaling mechanism at or close to the synapse. Examples of such ligands are the peptide growth factors which, on binding, activate receptor tyrosine kinases. To gain insight into the physiological consequences of receptor tyrosine kinase activation in squid giant synapse, a series of growth factors was tested in this preparation. Electrophysiological, pharmacological, and biochemical analysis demonstrated that nerve growth factor (NGF) triggers an acute and specific reduction of the postsynaptic potential amplitude, without affecting the presynaptic spike generation or presynaptic calcium current. The NGF target is localized at a postsynaptic site and involves a new TrkA-like receptor. The squid receptor crossreacts with antibodies generated against mammalian TrkA, is tyrosine phosphorylated in response to NGF stimulation, and is blocked by specific pharmacological inhibitors. The modulation described emphasizes the important role of growth factors on invertebrate synaptic transmission. PMID:9844004

  19. Nerve growth factor acutely reduces chemical transmission by means of postsynaptic TrkA-like receptors in squid giant synapse.

    PubMed

    Moreno, H; Nadal, M; Leznik, E; Sugimori, M; Lax, I; Schlessinger, J; Llinás, R

    1998-12-01

    Tyrosine phosphorylation has been shown to be an important modulator of synaptic transmission in both vertebrates and invertebrates. Such findings hint toward the existence of extracellular ligands capable of activating this widely represented signaling mechanism at or close to the synapse. Examples of such ligands are the peptide growth factors which, on binding, activate receptor tyrosine kinases. To gain insight into the physiological consequences of receptor tyrosine kinase activation in squid giant synapse, a series of growth factors was tested in this preparation. Electrophysiological, pharmacological, and biochemical analysis demonstrated that nerve growth factor (NGF) triggers an acute and specific reduction of the postsynaptic potential amplitude, without affecting the presynaptic spike generation or presynaptic calcium current. The NGF target is localized at a postsynaptic site and involves a new TrkA-like receptor. The squid receptor crossreacts with antibodies generated against mammalian TrkA, is tyrosine phosphorylated in response to NGF stimulation, and is blocked by specific pharmacological inhibitors. The modulation described emphasizes the important role of growth factors on invertebrate synaptic transmission.

  20. Comparison of acute non-visual bright light responses in patients with optic nerve disease, glaucoma and healthy controls

    PubMed Central

    Münch, M.; Léon, L.; Collomb, S.; Kawasaki, A.

    2015-01-01

    This study examined the effect of optic nerve disease, hence retinal ganglion cell loss, on non-visual functions related to melanopsin signalling. Test subjects were patients with bilateral visual loss and optic atrophy from either hereditary optic neuropathy (n = 11) or glaucoma (n = 11). We measured melatonin suppression, subjective sleepiness and cognitive functions in response to bright light exposure in the evening. We also quantified the post-illumination pupil response to a blue light stimulus. All results were compared to age-matched controls (n = 22). Both groups of patients showed similar melatonin suppression when compared to their controls. Greater melatonin suppression was intra-individually correlated to larger post-illumination pupil response in patients and controls. Only the glaucoma patients demonstrated a relative attenuation of their pupil response. In addition, they were sleepier with slower reaction times during nocturnal light exposure. In conclusion, glaucomatous, but not hereditary, optic neuropathy is associated with reduced acute light effects. At mild to moderate stages of disease, this is detected only in the pupil function and not in responses conveyed via the retinohypothalamic tract such as melatonin suppression. PMID:26478261

  1. N-11C-Methyl-Dopamine PET Imaging of Sympathetic Nerve Injury in a Swine Model of Acute Myocardial Ischemia: A Comparison with 13N-Ammonia PET

    PubMed Central

    Zhou, Weina; Wang, Xiangcheng; He, Yulin; Nie, Yongzhen; Zhang, Guojian; Wang, Cheng; Wang, Chunmei; Wang, Xuemei

    2016-01-01

    Objective. Using a swine model of acute myocardial ischemia, we sought to validate N-11C-methyl-dopamine (11C-MDA) as an agent capable of imaging cardiac sympathetic nerve injury. Methods. Acute myocardial ischemia was surgically generated in Chinese minipigs. ECG and serum enzyme levels were used to detect the presence of myocardial ischemia. Paired 11C-MDA PET and 13N-ammonia PET scans were performed at baseline, 1 day, and 1, 3, and 6 months after surgery to relate cardiac sympathetic nerve injury to blood perfusion. Results. Seven survived the surgical procedure. The ECG-ST segment was depressed, and levels of the serum enzymes increased. Cardiac uptake of tracer was quantified as the defect volume. Both before and immediately after surgery, the images obtained with 11C-MDA and 13N-ammonia were similar. At 1 to 6 months after surgery, however, 11C-MDA postsurgical left ventricular myocardial defect volume was significantly greater compared to 13N-ammonia. Conclusions. In the Chinese minipig model of acute myocardial ischemia, the extent of the myocardial defect as visualized by 11C-MDA is much greater than would be suggested by blood perfusion images, and the recovery from myocardial sympathetic nerve injury is much slower than the restoration of blood perfusion. 11C-MDA PET may provide additional biological information during recovery from ischemic heart disease. PMID:27034950

  2. [Electrical nerve stimulation for plexus and nerve blocks].

    PubMed

    Birnbaum, J; Klotz, E; Bogusch, G; Volk, T

    2007-11-01

    Despite the increasing use of ultrasound, electrical nerve stimulation is commonly used as the standard for both plexus and peripheral nerve blocks. Several recent randomized trials have contributed to a better understanding of physiological and clinical correlations. Traditionally used currents and impulse widths are better defined in relation to the distance between needle tip and nerves. Commercially available devices enable transcutaneous nerve stimulation and provide new opportunities for the detection of puncture sites and for training. The electrically ideal position of the needle usually is defined by motor responses which can not be interpreted without profound anatomical knowledge. For instance, interscalene blocks can be successful even after motor responses of deltoid or pectoral muscles. Infraclavicular blocks should be aimed at stimulation of the posterior fascicle (extension). In contrast to multiple single nerve blocks, axillary single-shot blocks more commonly result in incomplete anaesthesia. Blockade of the femoral nerve can be performed without any nerve stimulation if the fascia iliaca block is used. Independently of the various approaches to the sciatic nerve, inversion and plantar flexion are the best options for single-shot blocks. Further clinical trials are needed to define the advantages of stimulating catheters in continuous nerve blocks.

  3. Stationary wavelet transform and higher order statistical analyses of intrafascicular nerve recordings.

    PubMed

    Qiao, Shaoyu; Torkamani-Azar, Mastaneh; Salama, Paul; Yoshida, Ken

    2012-10-01

    Nerve signals were recorded from the sciatic nerve of the rabbits in the acute experiments with multi-channel thin-film longitudinal intrafascicular electrodes. 5.5 s sequences of quiescent and high-level nerve activity were spectrally decomposed by applying a ten-level stationary wavelet transform with the Daubechies 10 (Db10) mother wavelet. Then, the statistical distributions of the raw and subband-decomposed sequences were estimated and used to fit a fourth-order Pearson distribution as well as check for normality. The results indicated that the raw and decomposed background and high-level nerve activity distributions were nearly zero-mean and non-skew. All distributions with the frequency content above 187.5 Hz were leptokurtic except for the first-level decomposition representing frequencies in the subband between 12 and 24 kHz, which was Gaussian. This suggests that nerve activity acts to change the statistical distribution of the recording. The results further demonstrated that quiescent recording contained a mixture of an underlying pink noise and low-level nerve activity that could not be silenced. The signal-to-noise ratios based upon the standard deviation (SD) and kurtosis were estimated, and the latter was found as an effective measure for monitoring the nerve activity residing in different frequency subbands. The nerve activity modulated kurtosis along with SD, suggesting that the joint use of SD and kurtosis could improve the stability and detection accuracy of spike-detection algorithms. Finally, synthesizing the reconstructed subband signals following denoising based upon the higher order statistics of the subband-decomposed coefficient sequences allowed us to effectively purify the signal without distorting spike shape.

  4. Effect of Artificial Nerve Conduit Vascularization on Peripheral Nerve in a Necrotic Bed

    PubMed Central

    Iijima, Yuki; Murayama, Akira; Takeshita, Katsushi

    2016-01-01

    Background: Several types of artificial nerve conduit have been used for bridging peripheral nerve gaps as an alternative to autologous nerves. However, their efficacy in repairing nerve injuries accompanied by surrounding tissue damage remains unclear. We fabricated a novel nerve conduit vascularized by superficial inferior epigastric (SIE) vessels and evaluated whether it could promote axonal regeneration in a necrotic bed. Methods: A 15-mm nerve conduit was implanted beneath the SIE vessels in the groin of a rat to supply it with blood vessels 2 weeks before nerve reconstruction. We removed a 13-mm segment of the sciatic nerve and then pressed a heated iron against the dorsal thigh muscle to produce a burn. The defects were immediately repaired with an autograft (n = 10), nerve conduit graft (n = 8), or vascularized nerve conduit graft (n = 8). Recovery of motor function was examined for 18 weeks after surgery. The regenerated nerves were electrophysiologically and histologically evaluated. Results: The vascularity of the nerve conduit implanted beneath the SIE vessels was confirmed histologically 2 weeks after implantation. Between 14 and 18 weeks after surgery, motor function of the vascularized conduit group was significantly better than that of the nonvascularized conduit group. Electrophysiological and histological evaluations revealed that although the improvement did not reach the level of reinnervation achieved by an autograft, the vascularized nerve conduit improved axonal regeneration more than did the conduit alone. Conclusion: Vascularization of artificial nerve conduits accelerated peripheral nerve regeneration, but further research is required to improve the quality of nerve regeneration. PMID:27257595

  5. Ketoprofen combined with artery graft entubulization improves functional recovery of transected peripheral nerves.

    PubMed

    Mohammadi, Rahim; Mehrtash, Moein; Nikonam, Nima; Mehrtash, Moied; Amini, Keyvan

    2014-12-01

    The objective was to assess the local effect of ketoprofen on sciatic nerve regeneration and functional recovery. Eighty healthy male white Wistar rats were randomized into four experimental groups of 20 animals each: In the transected group (TC), the left sciatic nerve was transected and nerve cut ends were fixed in the adjacent muscle. In the treatment group the defect was bridged using an artery graft (AG/Keto) filled with 10 microliter ketoprofen (0.1 mg/kg). In the artery graft group (AG), the graft was filled with phosphated-buffer saline alone. In the sham-operated group (SHAM), the sciatic nerve was exposed and manipulated. Each group was subdivided into four subgroups of five animals each and regenerated nerve fibres were studied at 4, 8, 12 and 16 weeks post operation. Behavioural testing, sciatic nerve functional study, gastrocnemius muscle mass and morphometric indices showed earlier regeneration of axons in AG/Keto than in AG group (p < 0.05). Immunohistochemical study clearly showed more positive location of reactions to S-100 in AG/Keto than in AG group. When loaded in an artery graft, ketoprofen improved functional recovery and morphometric indices of the sciatic nerve. Local usage of this easily accessible therapeutic medicine is cost saving and avoids the problems associated with systemic administration.

  6. Adrenergic vasoconstriction in peripheral nerves of the rabbit

    SciTech Connect

    Selander, D.; Mansson, L.G.; Karlsson, L.; Svanvik, J.

    1985-01-01

    The blood flow in the sciatic nerve of the rabbit was estimated from the wash out of intraneurally injected /sup 133/Xe. To avoid diffusion of the tracer into the surrounding muscular tissue, the nerve was covered by a gas-tight plastic film. Using this technique, the basal blood flow in the sciatic nerve was estimated to 35 ml X min-1 X 100 g-1. It was found that intraarterial norepinephrine and electrical stimulation of the lumbar sympathetic chain strongly reduced the wash out of /sup 133/Xe, which only can be explained by a pronounced reduction of the blood flow in the nerve itself. The blood flow again increased within 4 min of stopping the infusion of norepinephrine or the sympathetic stimulation. The prolonged effect and higher neurotoxicity of local anesthetics containing adrenaline may be explained by an alpha receptor-mediated vasoconstriction of the microvessels of peripheral nerves.

  7. Surface treatment of silicone rubber by carbon negative-ion implantation for nerve regeneration

    NASA Astrophysics Data System (ADS)

    Tsuji, Hiroshi; Izukawa, Masayoshi; Ikeguchi, Ryosuke; Kakinoki, Ryosuke; Sato, Hiroko; Gotoh, Yasuhito; Ishikawa, Junzo

    2004-07-01

    Surface treatment of silicone rubber by carbon negative ion-implantation was investigated for nerve regeneration by "tubulation". Silicone rubber had its surface property altered to be more hydrophilic by carbon negative-ion implantation. The extracellular matrices of proteins in culture medium adsorbed on the implanted surface rather than unimplanted ones. These improvements in wettability and adsorption properties of proteins were respected to contribute to the regeneration of a nerve-lacking system. An in vivo regeneration test of rat sciatic nerves with silicone-rubber tubes was performed. Using a tube in which the inner surface was implanted with carbon negative ions, the sciatic nerve was regenerated through the inter-stump gap of 15 mm between the proximal and distal nerve stumps and electrical stimulation was transported through the regenerated nerve. Thus, the nerve system was recovered. However, with the unimplanted tube, the nerve was not regenerated at all.

  8. Let-7 microRNAs Regenerate Peripheral Nerve Regeneration by Targeting Nerve Growth Factor

    PubMed Central

    Li, Shiying; Wang, Xinghui; Gu, Yun; Chen, Chu; Wang, Yaxian; Liu, Jie; Hu, Wen; Yu, Bin; Wang, Yongjun; Ding, Fei; Liu, Yan; Gu, Xiaosong

    2015-01-01

    Peripheral nerve injury is a common clinical problem. Nerve growth factor (NGF) promotes peripheral nerve regeneration, but its clinical applications are limited by several constraints. In this study, we found that the time-dependent expression profiles of eight let-7 family members in the injured nerve after sciatic nerve injury were roughly similar to each other. Let-7 microRNAs (miRNAs) significantly reduced cell proliferation and migration of primary Schwann cells (SCs) by directly targeting NGF and suppressing its protein translation. Following sciatic nerve injury, the temporal change in let-7 miRNA expression was negatively correlated with that in NGF expression. Inhibition of let-7 miRNAs increased NGF secretion by primary cultured SCs and enhanced axonal outgrowth from a coculture of primary SCs and dorsal root gangalion neurons. In vivo tests indicated that let-7 inhibition promoted SCs migration and axon outgrowth within a regenerative microenvironment. In addition, the inhibitory effect of let-7 miRNAs on SCs apoptosis might serve as an early stress response to nerve injury, but this effect seemed to be not mediated through a NGF-dependent pathway. Collectively, our results provide a new insight into let-7 miRNA regulation of peripheral nerve regeneration and suggest a potential therapy for repair of peripheral nerve injury. PMID:25394845

  9. Early Electrodiagnostic Features of Upper Extremity Sensory Nerves Can Differentiate Axonal Guillain-Barré Syndrome from Acute Inflammatory Demyelinating Polyneuropathy

    PubMed Central

    Koo, Yong Seo; Shin, Ha Young; Kim, Jong Kuk; Nam, Tai-Seung; Shin, Kyong Jin; Bae, Jong-Seok; Suh, Bum Chun; Oh, Jeeyoung; Yoon, Byeol-A

    2016-01-01

    Background and Purpose Serial nerve conduction studies (NCSs) are recommended for differentiating axonal and demyelinating Guillain-Barré syndrome (GBS), but this approach is not suitable for early diagnoses. This study was designed to identify possible NCS parameters for differentiating GBS subtypes. Methods We retrospectively reviewed the medical records of 70 patients with GBS who underwent NCS within 10 days of symptom onset. Patients with axonal GBS and acute inflammatory demyelinating polyneuropathy (AIDP) were selected based on clinical characteristics and serial NCSs. An antiganglioside antibody study was used to increase the diagnostic certainty. Results The amplitudes of median and ulnar nerve sensory nerve action potentials (SNAPs) were significantly smaller in the AIDP group than in the axonal-GBS group. Classification and regression-tree analysis revealed that the distal ulnar sensory nerve SNAP amplitude was the best predictor of axonal GBS. Conclusions Early upper extremity sensory NCS findings are helpful in differentiating axonal-GBS patients with antiganglioside antibodies from AIDP patients.

  10. Silencing the α2 subunit of GABAA receptors in rat dorsal root ganglia reveals its major role in antinociception post-traumatic nerve injury

    PubMed Central

    Obradović, Aleksandar LJ; Scarpa, Joseph; Osuru, Hari P; Weaver, Janelle L; Park, Ji-Yong; Pathirathna, Sriyani; Peterkin, Alexander; Lim, Yunhee; Jagodic, Miljenko M; Todorovic, Slobodan M; Jevtovic-Todorovic, Vesna

    2015-01-01

    Background Neuropathic pain is likely the result of repetitive high frequency bursts of peripheral afferent activity leading to long-lasting changes in synaptic plasticity in the spinal dorsal horn (DH). Drugs that promote GABA activity in the DH provide partial relief of neuropathic symptoms. We examined how in vivo silencing of the GABAA α2 gene in DRG controls of NPP. Methods After crush injury to the right sciatic nerve of female rats, the α2 GABAA antisense and mismatch oligodeoxynucleotides or NO-711 (a GABA uptake inhibitor) were applied to the L5 DRG. In vivo behavioral assessment of nociception was conducted prior to the injury and ensuing 10 days (n=4–10). In vitro quantification of α2 GABAA protein and electrophysiology studies of GABAA currents were performed on acutely dissociated L5 DRG neurons at relevant time-points (n=6–14). Results NPP post-crush injury of a sciatic nerve in adult female rats coincides with significant down-regulation of the α2 subunit expression in the ipsilateral DRG (about 30%). Selective down-regulation of α2 expression in DRGs significantly worsens mechanical (2.55±0.75 to 5.16±1.16) and thermal (7.97±0.96 to 5.51±0.75) hypersensitivity in crush-injured animals and causes development of significant mechanical (2.33±0.40 to 5.00±0.33) and thermal (10.80±0.29 to 7.34±0.81) hypersensitivity in sham animals (data shown as MEAN±SD). Conversely, up-regulation of endogenous GABA via blockade of its uptake in DRG alleviates NPP. Conclusions The GABAA receptor in the DRG plays an important role in pathophysiology of NPP caused by sciatic nerve injury and represent promising target for novel pain therapies. PMID:26164299

  11. Cartilage oligomeric matrix protein enhances the vascularization of acellular nerves

    PubMed Central

    Cui, Wei-ling; Qiu, Long-hai; Lian, Jia-yan; Li, Jia-chun; Hu, Jun; Liu, Xiao-lin

    2016-01-01

    Vascularization of acellular nerves has been shown to contribute to nerve bridging. In this study, we used a 10-mm sciatic nerve defect model in rats to determine whether cartilage oligomeric matrix protein enhances the vascularization of injured acellular nerves. The rat nerve defects were treated with acellular nerve grafting (control group) alone or acellular nerve grafting combined with intraperitoneal injection of cartilage oligomeric matrix protein (experimental group). As shown through two-dimensional imaging, the vessels began to invade into the acellular nerve graft from both anastomotic ends at day 7 post-operation, and gradually covered the entire graft at day 21. The vascular density, vascular area, and the velocity of revascularization in the experimental group were all higher than those in the control group. These results indicate that cartilage oligomeric matrix protein enhances the vascularization of acellular nerves. PMID:27127495

  12. Calcium regulation in frog peripheral nerve by the blood-nerve barrier

    SciTech Connect

    Wadhwani, K.C.

    1986-01-01

    The objectives of this research were: (a) to investigate the characteristics of calcium transport across the perineurium and the endoneurial capillaries, and (b) to gain a better understanding of the extent of calcium homeostasis in the endoneurial space. To study the nature of calcium transport across the perineurium, the flux of radiotracer /sup 45/Ca was measured through the perineurial cylinder, isolated from the frog sciatic nerve, and through the perineurium into the nerve in situ. To study the nature of calcium transport across the endoneurial capillaries, the permeability-surface area product (PA) of /sup 45/Ca was determined as a function of the calcium concentration in the blood. To study calcium homeostasis, the calcium content of the frog sciatic nerve was determined as a function of chronic changes in plasma (Ca).

  13. Experimental study of vein subvolution combined with neural stem cells to repair sciatic neurologic defects in rats

    PubMed Central

    Li, Kang; Jiang, Yan; Jiang, Dianming

    2015-01-01

    This study aims to explore the effects of vein subvolution combined with neural stem cells on nerve regeneration. Animal model of sciatic nerve defects was established with SD rats. A total of 63 SD rats were divided into control group, vein subvolution group (treatment 1 group) and vein subvolution combined with neural stem cells group (treatment 2 group). The recovery of neurological function after 12 weeks was evaluated by nerve electrophysiological technique, histological observation and other methods. The recovery degree of sciatic nerve defect in treatment 2 group was better than that of other groups; The SFI values significantly decreased in treatment 2 group after 8 weeks; the regenerative nerve fiber numbers in treatment 2 group were significant higher than that of other groups; the recovery rates of treatment 1 and 2 groups were significant higher than that of control group. The effects of vein subvolution combined with neural stem cells on repairing peripheral nerve defects were better than that of vein subvolution method. PMID:26617811

  14. Reasonable classical concepts in human lower limb anatomy from the viewpoint of the primitive persistent sciatic artery and twisting human lower limb.

    PubMed

    Kawashima, Tomokazu; Sasaki, Hiroshi

    2010-11-01

    The main aim of this review is (1) to introduce the two previous studies we published human lower limb anatomy based on the conventional macroscopic anatomical [corrected] criteria with hazardous recognition of this description, (2) to activate the discussion whether the limb homology exists, and (3) to contribute to future study filling the gap between the gross anatomy and embryology. One of the topics we discussed was the human persistent sciatic artery. To date, numerous human cases of persistent sciatic artery have been reported in which the anomalous artery was present in the posterior compartment of the thigh alongside the sciatic nerve. As one of the important criteria for assessing the human primitive sciatic artery, its ventral arterial position with respect to the sciatic nerve is reasonable based on the initial positional relationship between ventral arterial and dorsal nervous systems and comparative anatomical findings. We also discuss ways of considering the topography of muscles of the lower limb and their innervations compared to those of the upper limb. We propose a schema of the complex anatomical characteristics of the lower limb based on the vertebrate body plan. According to this reasonable schema, the twisted anatomy of the lower limb can be understood more easily. These two main ideas discussed in this paper will be useful for further understanding of the anatomy of the lower limb and as a first step for future. We hope that the future study in lower limb will be further developed by both viewpoints of the classical gross anatomy and recent embryology.

  15. Coordinated, multi-joint, fatigue-resistant feline stance produced with intrafascicular hind limb nerve stimulation

    NASA Astrophysics Data System (ADS)

    Normann, R. A.; Dowden, B. R.; Frankel, M. A.; Wilder, A. M.; Hiatt, S. D.; Ledbetter, N. M.; Warren, D. A.; Clark, G. A.

    2012-04-01

    The production of graceful skeletal movements requires coordinated activation of multiple muscles that produce torques around multiple joints. The work described herein is focused on one such movement, stance, that requires coordinated activation of extensor muscles acting around the hip, knee and ankle joints. The forces evoked in these muscles by external stimulation all have a complex dependence on muscle length and shortening velocities, and some of these muscles are biarticular. In order to recreate sit-to-stand maneuvers in the anesthetized feline, we excited the hind limb musculature using intrafascicular multielectrode stimulation (IFMS) of the muscular branch of the sciatic nerve, the femoral nerve and the main branch of the sciatic nerve. Stimulation was achieved with either acutely or chronically implanted Utah Slanted Electrode Arrays (USEAs) via subsets of electrodes (1) that activated motor units in the extensor muscles of the hip, knee and ankle joints, (2) that were able to evoke large extension forces and (3) that manifested minimal coactivation of the targeted motor units. Three hind limb force-generation strategies were investigated, including sequential activation of independent motor units to increase force, and interleaved or simultaneous IFMS of three sets of six or more USEA electrodes that excited the hip, knee and ankle extensors. All force-generation strategies evoked stance, but the interleaved IFMS strategy also reduced muscle fatigue produced by repeated sit-to-stand maneuvers compared with fatigue produced by simultaneous activation of different motor neuron pools. These results demonstrate the use of interleaved IFMS as a means to recreate coordinated, fatigue-resistant multi-joint muscle forces in the unilateral hind limb. This muscle activation paradigm could provide a promising neuroprosthetic approach for the restoration of sit-to-stand transitions in individuals who are paralyzed by spinal cord injury, stroke or disease.

  16. Sensitivity Analysis of Vagus Nerve Stimulation Parameters on Acute Cardiac Autonomic Responses: Chronotropic, Inotropic and Dromotropic Effects

    PubMed Central

    Ojeda, David; Le Rolle, Virginie; Romero-Ugalde, Hector M.; Gallet, Clément; Bonnet, Jean-Luc; Henry, Christine; Bel, Alain; Mabo, Philippe; Carrault, Guy; Hernández, Alfredo I.

    2016-01-01

    Although the therapeutic effects of Vagus Nerve Stimulation (VNS) have been recognized in pre-clinical and pilot clinical studies, the effect of different stimulation configurations on the cardiovascular response is still an open question, especially in the case of VNS delivered synchronously with cardiac activity. In this paper, we propose a formal mathematical methodology to analyze the acute cardiac response to different VNS configurations, jointly considering the chronotropic, dromotropic and inotropic cardiac effects. A latin hypercube sampling method was chosen to design a uniform experimental plan, composed of 75 different VNS configurations, with different values for the main parameters (current amplitude, number of delivered pulses, pulse width, interpulse period and the delay between the detected cardiac event and VNS onset). These VNS configurations were applied to 6 healthy, anesthetized sheep, while acquiring the associated cardiovascular response. Unobserved VNS configurations were estimated using a Gaussian process regression (GPR) model. In order to quantitatively analyze the effect of each parameter and their combinations on the cardiac response, the Sobol sensitivity method was applied to the obtained GPR model and inter-individual sensitivity markers were estimated using a bootstrap approach. Results highlight the dominant effect of pulse current, pulse width and number of pulses, which explain respectively 49.4%, 19.7% and 6.0% of the mean global cardiovascular variability provoked by VNS. More interestingly, results also quantify the effect of the interactions between VNS parameters. In particular, the interactions between current and pulse width provoke higher cardiac effects than the changes on the number of pulses alone (between 6 and 25% of the variability). Although the sensitivity of individual VNS parameters seems similar for chronotropic, dromotropic and inotropic responses, the interacting effects of VNS parameters provoke

  17. Effects of lead acetate on guinea pig - cochear microphonics, action potential, and motor nerve conduction velocity

    SciTech Connect

    Yamamura, K.; Maehara, N.; Terayama, K.; Ueno, N.; Kohyama, A.; Sawada, Y.; Kishi, R.

    1987-04-01

    Segmental demyelination and axonal degeneration of motor nerves induced by lead exposure is well known in man, and animals. The effect of lead acetate exposure to man may involve the cranial nerves, since vertigo and sensory neuronal deafness have been reported among lead workers. However, there are few reports concerning the dose-effects of lead acetate both to the peripheral nerve and the cranial VII nerve with measurement of blood lead concentration. The authors investigated the effects of lead acetate to the cochlea and the VIII nerve using CM (cochlear microphonics) and AP (action potential) of the guinea pigs. The effects of lead acetate to the sciatic nerve were measured by MCV of the sciatic nerve with measurement of blood lead concentration.

  18. Peripheral nerve morphogenesis induced by scaffold micropatterning

    PubMed Central

    Memon, Danish; Boneschi, Filippo Martinelli; Madaghiele, Marta; Brambilla, Paola; Del Carro, Ubaldo; Taveggia, Carla; Riva, Nilo; Trimarco, Amelia; Lopez, Ignazio D.; Comi, Giancarlo; Pluchino, Stefano; Martino, Gianvito; Sannino, Alessandro; Quattrini, Angelo

    2014-01-01

    Several bioengineering approaches have been proposed for peripheral nervous system repair, with limited results and still open questions about the underlying molecular mechanisms. We assessed the biological processes that occur after the implantation of collagen scaffold with a peculiar porous microstructure of the wall in a rat sciatic nerve transection model compared to commercial collagen conduits and nerve crush injury using functional, histological and genome wide analyses. We demonstrated that within 60 days, our conduit had been completely substituted by a normal nerve. Gene expression analysis documented a precise sequential regulation of known genes involved in angiogenesis, Schwann cells/axons interactions and myelination, together with a selective modulation of key biological pathways for nerve morphogenesis induced by porous matrices. These data suggest that the scaffold’s microstructure profoundly influences cell behaviors and creates an instructive micro-environment to enhance nerve morphogenesis that can be exploited to improve recovery and understand the molecular differences between repair and regeneration. PMID:24559639

  19. Collagenosis in wallerian degeneration depends on peripheral nerve type.

    PubMed

    Eather, T F; Pollock, M

    1988-06-01

    In the mature rat we determined the extent of peripheral nerve collagenosis in response to Wallerian degeneration and examined whether or not nonfibroblastic elements such as Schwann cells were important. Collagen was estimated as the hydroxy-proline content of normal and axotomized nerve fascicles after single or double crush lesions of both myelinated and unmyelinated nerves. Crushed unmyelinated nerve produced two to four times more collagen relative to control nerve than did the sciatic nerve. The nature of the interaction between two successive crushes was different in the two nerves. These results suggest that the degree of collagen fibrillogenesis occurring in Wallerian degeneration is dependent on peripheral nerve type and that the presence of myelin is not necessary for collagen fibrillogenesis.

  20. Myelinated mouse nerves studied by X-ray phase contrast zoom tomography.

    PubMed

    Bartels, M; Krenkel, M; Cloetens, P; Möbius, W; Salditt, T

    2015-12-01

    We have used X-ray phase contrast tomography to resolve the structure of uncut, entire myelinated optic, saphenous and sciatic mouse nerves. Intrinsic electron density contrast suffices to identify axonal structures. Specific myelin labeling by an osmium tetroxide stain enables distinction between axon and surrounding myelin sheath. Utilization of spherical wave illumination enables zooming capabilities which enable imaging of entire sciatic internodes as well as identification of sub-structures such as nodes of Ranvier and Schmidt-Lanterman incisures. PMID:26546551

  1. Myelinated mouse nerves studied by X-ray phase contrast zoom tomography.

    PubMed

    Bartels, M; Krenkel, M; Cloetens, P; Möbius, W; Salditt, T

    2015-12-01

    We have used X-ray phase contrast tomography to resolve the structure of uncut, entire myelinated optic, saphenous and sciatic mouse nerves. Intrinsic electron density contrast suffices to identify axonal structures. Specific myelin labeling by an osmium tetroxide stain enables distinction between axon and surrounding myelin sheath. Utilization of spherical wave illumination enables zooming capabilities which enable imaging of entire sciatic internodes as well as identification of sub-structures such as nodes of Ranvier and Schmidt-Lanterman incisures.

  2. Three-dimensional conductive constructs for nerve regeneration.

    PubMed

    George, Paul M; Saigal, Rajiv; Lawlor, Michael W; Moore, Michael J; LaVan, David A; Marini, Robert P; Selig, Martin; Makhni, Melvin; Burdick, Jason A; Langer, Robert; Kohane, Daniel S

    2009-11-01

    The unique electrochemical properties of conductive polymers can be utilized to form stand-alone polymeric tubes and arrays of tubes that are suitable for guides to promote peripheral nerve regeneration. Noncomposite, polypyrrole (PPy) tubes ranging in inner diameter from 25 microm to 1.6 mm as well as multichannel tubes were fabricated by electrodeposition. While oxidation of the pyrrole monomer causes growth of the film, brief subsequent reduction allowed mechanical dissociation from the electrode mold, creating a stand-alone, conductive PPy tube. Conductive polymer nerve guides made in this manner were placed in transected rat sciatic nerves and shown to support nerve regeneration over an 8-week time period.

  3. Surgical anatomy of the retroperitoneal spaces, Part IV: retroperitoneal nerves.

    PubMed

    Mirilas, Petros; Skandalakis, John E

    2010-03-01

    We present surgicoanatomical topographic relations of nerves and plexuses in the retroperitoneal space: 1) six named parietal nerves, branches of the lumbar plexus: iliohypogastric, ilioinguinal, genitofemoral, lateral femoral cutaneous, obturator, femoral. 2) The sacral plexus is formed by the lumbosacral trunk, ventral rami of S1-S3, and part of S4; the remainder of S4 joining the coccygeal plexus. From this plexus originate the superior gluteal nerve, which passes backward through the greater sciatic foramen above the piriformis muscle; the inferior gluteal nerve also courses through the greater sciatic foramen, but below the piriformis; 3) sympathetic trunks: right and left lumbar sympathetic trunks, which comprise four interconnected ganglia, and the pelvic chains; 4) greater, lesser, and least thoracic splanchnic nerves (sympathetic), which pass the diaphragm and join celiac ganglia; 5) four lumbar splanchnic nerves (sympathetic), which arise from lumbar sympathetic ganglia; 6) pelvic splanchnic nerves (nervi erigentes), providing parasympathetic innervation to the descending colon and pelvic splanchna; and 7) autonomic (prevertebral) plexuses, formed by the vagus nerves, splanchnic nerves, and ganglia (celiac, superior mesenteric, aorticorenal). They include sympathetic, parasympathetic, and sensory (mainly pain) fibers. The autonomic plexuses comprise named parts: aortic, superior mesenteric, inferior mesenteric, superior hypogastric, and inferior hypogastric (hypogastric nerves).

  4. ACUTE LESION OF THE MOTOR BRANCH OF THE ULNAR NERVE IN THE WRIST AFTER TUG-OF-WAR TRAINING

    PubMed Central

    Seguti, Vladimir Ferreira; Bonavides, Aloísio Fernandes; Flores, Leandro Pretto; Ferreira, Lisiane Seguti

    2015-01-01

    Papers correlating clinical and electrophysiological findings relating to ulnar nerve lesions in the wrist are uncommon in the literature, if compared with elbow injuries. We present the case of a patient with atrophy of the intrinsic musculature of the hand, secondary to injury only of the motor branch of the ulnar nerve, which is located in Guyon's canal close to the hamate hook. We review the anatomical, clinical and neurophysiological aspects of distal ulnar nerve injuries and we emphasize the importance of multidisciplinary approaches. Specifically in relation to the mechanism of injury of this patient (tug-of-war), we did not find any similar cases in the literature. We issue an alert regarding the risks during military physical training. PMID:27047837

  5. Nerve Transfers for the Restoration of Wrist, Finger, and Thumb Extension After High Radial Nerve Injury.

    PubMed

    Pet, Mitchell A; Lipira, Angelo B; Ko, Jason H

    2016-05-01

    High radial nerve injury is a common pattern of peripheral nerve injury most often associated with orthopedic trauma. Nerve transfers to the wrist and finger extensors, often from the median nerve, offer several advantages when compared to nerve repair or grafting and tendon transfer. In this article, we discuss the forearm anatomy pertinent to performing these nerve transfers and review the literature surrounding nerve transfers for wrist, finger, and thumb extension. A suggested algorithm for management of acute traumatic high radial nerve palsy is offered, and our preferred surgical technique for treatment of high radial nerve palsy is provided. PMID:27094891

  6. Peptide therapy with pentadecapeptide BPC 157 in traumatic nerve injury.

    PubMed

    Gjurasin, Miroslav; Miklic, Pavle; Zupancic, Bozidar; Perovic, Darko; Zarkovic, Kamelija; Brcic, Luka; Kolenc, Danijela; Radic, Bozo; Seiwerth, Sven; Sikiric, Predrag

    2010-02-25

    We focused on the healing of rat transected sciatic nerve and improvement made by stable gastric pentadecapeptide BPC 157 (10 microg, 10ng/kg) applied shortly after injury (i) intraperitoneally/intragastrically/locally, at the site of anastomosis, or after (ii) non-anastomozed nerve tubing (7 mm nerve segment resected) directly into the tube. Improvement was shown clinically (autotomy), microscopically/morphometrically and functionally (EMG, one or two months post-injury, walking recovery (sciatic functional index (SFI)) at weekly intervals). BPC 157-rats exhibited faster axonal regeneration: histomorphometrically (improved presentation of neural fascicles, homogeneous regeneration pattern, increased density and size of regenerative fibers, existence of epineural and perineural regeneration, uniform target orientation of regenerative fibers, and higher proportion of neural vs. connective tissue, all fascicles in each nerve showed increased diameter of myelinated fibers, thickness of myelin sheet, number of myelinated fibers per area and myelinated fibers as a percentage of the nerve transected area and the increased blood vessels presentation), electrophysiologically (increased motor action potentials), functionally (improved SFI), the autotomy absent. Thus, BPC 157 markedly improved rat sciatic nerve healing. PMID:19903499

  7. West Nile virus-induced acute flaccid paralysis is prevented by monoclonal antibody treatment when administered after infection of spinal cord neurons.

    PubMed

    Morrey, John D; Siddharthan, Venkatraman; Wang, Hong; Hall, Jeffery O; Skirpstunas, Ramona T; Olsen, Aaron L; Nordstrom, Jeffrey L; Koenig, Scott; Johnson, Syd; Diamond, Michael S

    2008-04-01

    Acute flaccid polio-like paralysis occurs during natural West Nile virus (WNV) infection in a subset of cases in animals and humans. To evaluate the pathology and the possibility for therapeutic intervention, the authors developed a model of acute flaccid paralysis by injecting WNV directly into the sciatic nerve or spinal cord of hamsters. By directly injecting selected sites of the nervous system with WNV, the authors mapped the lesions responsible for hind limb paralysis to the lumbar spinal cord. Immunohistochemical analysis of spinal cord sections from paralyzed hamsters revealed that WNV-infected neurons localized primarily to the ventral motor horn of the gray matter, consistent with the polio-like clinical presentation. Neuronal apoptosis and diminished cell function were identified by TUNEL (terminal deoxynucleotidyl transferase-mediated BrdUTP nick end labeling) and choline acetyltransferase staining, respectively. Administration of hE16, a potently neutralizing humanized anti-WNV monoclonal antibody, 2 to 3 days after direct WNV infection of the spinal cord, significantly reduced paralysis and mortality. Additionally, a single injection of hE16 as late as 5 days after WNV inoculation of the sciatic nerve also prevented paralysis. Overall, these experiments establish that WNV-induced acute flaccid paralysis in hamsters is due to neuronal infection and injury in the lumbar spinal cord and that treatment with a therapeutic antibody prevents paralysis when administered after WNV infection of spinal cord neurons. PMID:18444087

  8. Angelica injection promotes peripheral nerve structure and function recovery with increased expressions of nerve growth factor and brain derived neurotrophic factor in diabetic rats.

    PubMed

    Li, Ruilin; Zhang, Junjian; Zhang, Lei; Cui, Qin; Liu, Hui

    2010-08-01

    Several nervous system injury models, such as sciatic crush and chronic cerebral hypoperfusion have been well studied in terms of neuroprotective effect of angelica injection. However, definitive experimental studies are lacking on diabetic peripheral neuropathy (DPN). This study sought to investigate the effects of angelica injection on DPN in type 1 diabetic rats. Diabetes was induced by single intraperitoneal injection of streptozotocin (STZ). To examine whether DPN model succeeded, tail-flick latency (TFL) and motor nerve conduction velocity (MNCV) were measured at 6 weeks after diabetes induction. Then, diabetic rats were treated with high- and low-dose angelica injection for 4 weeks. TFL, MNCV, morphology of sciatic nerve, myelinated nerve fiber density and the expressions of nerve growth factor (NGF) and brain derived neurotrophic factor (BDNF) in soleus and sciatic nerve were measured at 10 weeks after diabetes induction. The results showed the TFL was significantly shortened (p<0.001) and the MNCV was reduced (p<0.01) in diabetic rats compared with normal control rats at 6 weeks after diabetes induction. The TFL was obviously prolonged and the MNCV was further reduced in diabetic control group at 10 weeks after diabetes induction. TFL, MNCV and morphology of sciatic nerve were remarkably ameliorated and myelinated nerve fiber density and the expressions of NGF and BDNF in soleus and sciatic nerve were increased in the angelica treatment groups. This study suggests angelica injection has potential therapeutic effects on DPN, and the mechanism might be related to direct increase in NGF expression and direct or indirect increase in BDNF expression.

  9. Differential fiber-specific block of nerve conduction in mammalian peripheral nerves using kilohertz electrical stimulation

    PubMed Central

    Patel, Yogi A.

    2015-01-01

    Kilohertz electrical stimulation (KES) has been shown to induce repeatable and reversible nerve conduction block in animal models. In this study, we characterized the ability of KES stimuli to selectively block specific components of stimulated nerve activity using in vivo preparations of the rat sciatic and vagus nerves. KES stimuli in the frequency range of 5–70 kHz and amplitudes of 0.1–3.0 mA were applied. Compound action potentials were evoked using either electrical or sensory stimulation, and block of components was assessed through direct nerve recordings and muscle force measurements. Distinct observable components of the compound action potential had unique conduction block thresholds as a function of frequency of KES. The fast component, which includes motor activity, had a monotonically increasing block threshold as a function of the KES frequency. The slow component, which includes sensory activity, showed a nonmonotonic block threshold relationship with increasing KES frequency. The distinct trends with frequency of the two components enabled selective block of one component with an appropriate choice of frequency and amplitude. These trends in threshold of the two components were similar when studying electrical stimulation and responses of the sciatic nerve, electrical stimulation and responses of the vagus nerve, and sensorimotor stimulation and responses of the sciatic nerve. This differential blocking effect of KES on specific fibers can extend the applications of KES conduction block to selective block and stimulation of neural signals for neuromodulation as well as selective control of neural circuits underlying sensorimotor function. PMID:25878155

  10. Lithium enhances remyelination of peripheral nerves

    PubMed Central

    Makoukji, Joelle; Belle, Martin; Meffre, Delphine; Stassart, Ruth; Grenier, Julien; Shackleford, Ghjuvan'Ghjacumu; Fledrich, Robert; Fonte, Cosima; Branchu, Julien; Goulard, Marie; de Waele, Catherine; Charbonnier, Frédéric; Sereda, Michael W.; Baulieu, Etienne-Emile; Schumacher, Michael; Bernard, Sophie; Massaad, Charbel

    2012-01-01

    Glycogen synthase kinase 3β (GSK3β) inhibitors, especially the mood stabilizer lithium chloride, are also used as neuroprotective or anti-inflammatory agents. We studied the influence of LiCl on the remyelination of peripheral nerves. We showed that the treatment of adult mice with LiCl after facial nerve crush injury stimulated the expression of myelin genes, restored the myelin structure, and accelerated the recovery of whisker movements. LiCl treatment also promoted remyelination of the sciatic nerve after crush. We also demonstrated that peripheral myelin gene MPZ and PMP22 promoter activities, transcripts, and protein levels are stimulated by GSK3β inhibitors (LiCl and SB216763) in Schwann cells as well as in sciatic and facial nerves. LiCl exerts its action in Schwann cells by increasing the amount of β-catenin and provoking its nuclear localization. We showed by ChIP experiments that LiCl treatment drives β-catenin to bind to T-cell factor/lymphoid-enhancer factor response elements identified in myelin genes. Taken together, our findings open perspectives in the treatment of nerve demyelination by administering GSK3β inhibitors such as lithium. PMID:22355115

  11. Electron microscope and x-ray diffraction studies of the effects of dehydration on the structure of nerve myelin. II. Optic nerve.

    PubMed

    FINEAN, J B

    1960-09-01

    The dehydration of rat optic nerve has been studied by allowing specimens to become partially or fully dried before fixation and preparation for electron microscopy. A correlation is established between electron micrographs of the myelin sheath and corresponding small-angle x-ray diffraction patterns. The modifications of the optic nerve myelin layers during drying were very similar to those described in more detail for the myelin of frog sciatic nerve. The most striking difference was that the system of fine layers characteristic of the fully dried myelin was much more extensive in the case of the optic nerve, and the layer thickness was significantly greater than the corresponding layer in the frog sciatic nerve preparation. The significance of these correlations is discussed.

  12. Acute abducens nerve palsy as a presenting feature in carotid-cavernous fistula in a 6-year-old girl

    PubMed Central

    Pawar, Neelam; Ramakrishanan, R.; Maheshwari, Devendra; Ravindran, Meenakshi

    2013-01-01

    Carotid-cavernous fistulas (CCF) are abnormal communications between the internal carotid artery and the cavernous sinus. Traumatic carotid-cavernous fistulae are rare potential complications of craniofacial trauma. Typical findings of CCF are proptosis, chemosis, headache, oculomotor or abducens nerve palsy, trigeminal pain and pulsating bruit over the temporal skull and the bulb. CCF are reported very rarely in childhood. This report describes the clinical and radiological findings of a pediatric patient presented with CCF.

  13. Acute abducens nerve palsy as a presenting feature in carotid-cavernous fistula in a 6-year-old girl

    PubMed Central

    Pawar, Neelam; Ramakrishanan, R.; Maheshwari, Devendra; Ravindran, Meenakshi

    2013-01-01

    Carotid-cavernous fistulas (CCF) are abnormal communications between the internal carotid artery and the cavernous sinus. Traumatic carotid-cavernous fistulae are rare potential complications of craniofacial trauma. Typical findings of CCF are proptosis, chemosis, headache, oculomotor or abducens nerve palsy, trigeminal pain and pulsating bruit over the temporal skull and the bulb. CCF are reported very rarely in childhood. This report describes the clinical and radiological findings of a pediatric patient presented with CCF. PMID:27625935

  14. Changes in nerve conduction and Pi/PCr ratio during denervation-reinnervation of the gastrocsoleus muscles of rats

    NASA Technical Reports Server (NTRS)

    Lai, K. S.; Jaweed, M. M.; Seestead, R.; Herbison, G. J.; Ditunno, J. F. Jr; McCully, K.; Chance, B.

    1992-01-01

    The purpose of this investigation was to study the changes in nerve conduction and phosphate metabolites of the gastrocsoleus muscles of rats during denervation-reinnervation. Sixteen male Sprague-Dawley rats underwent unilateral crush-denervation of the left sciatic nerves at the sciatic notch. Six rats were used for measurement of motor conduction latency and action potential amplitude of the gastrocsoleus muscle by stimulating the sciatic nerve at one, two and eight weeks after nerve crush. The other ten rats were designated for evaluation of the ratio of inorganic phosphorous (Pi) to phosphocreatine (PCr) by a 31P-phosphoenergetic spectrometer at two weeks and eight weeks after nerve crush. None of the sciatic nerves showed conduction to the gastrocsoleus at one or two weeks after nerve crush. At eight weeks postcrush, the motor conduction latency returned to within normal limits, whereas the action potential amplitude was only 55% of the normal. For the eight-week period of study, the Pi/PCr ratio of the normal control muscles ranged between 0.09 +/- 0.02 and 0.11 +/- 0.02 (mean +/- SD). The denervated muscles showed an increase of Pi/PCr ratio by 54% at two weeks postcrush, compared to the respective contralateral control sides. The ratios returned to the normal value by eight weeks postcrush. In summary, these data suggested that the metabolic recovery of the crush-denervated muscle followed the same pattern as the parameters of nerve conduction.

  15. Chronic histological effects of the flat interface nerve electrode

    NASA Astrophysics Data System (ADS)

    Leventhal, Daniel K.; Cohen, Mark; Durand, Dominique M.

    2006-06-01

    The flat interface nerve electrode (FINE) is designed to reshape peripheral nerves into favorable geometries for selective stimulation. Compared to cylindrical geometries, the ovoid geometries created by the FINE allow more space for contact placement. Furthermore, the amount of electrically excitable tissue between stimulating contacts and target axons is reduced. In this study, the nerve response to the presence of the FINE is examined histologically. Three different FINEs were designed to reshape peripheral nerves to different opening heights designated as 'wide' (1.3 mm), 'medium' (0.5 mm) and 'narrow' (0.1 mm) cuffs. Twelve adult cats were implanted with one cuff each (four in total of each design) on their right sciatic nerves. At least 3 months later, the animals were sacrificed and their sciatic nerves were harvested for histological evaluation. Cross-sectional areas and eccentricities (defined as the major axis divided by the minor axis of the closest fit ellipse to a region) of the nerves were measured to assess the degree of reshaping. The wide and medium cuff designs significantly reshaped the nerves compared to control nerves, though there was no significant difference in eccentricity between nerves implanted with wide and medium cuffs. There was extensive deposition of connective tissue in the epineurium of all nerves implanted with cuffs. No significant difference in fiber counts was measured in any of the groups studied. Only nerves implanted with narrow cuffs showed evidence of axonal injury and/or demyelination. These results, coupled with stimulation selectivity measurements made on the same animals, suggest that safe, selective electrodes can be designed with ovoid geometries. Moderate reshaping caused no damage, while extreme reshaping generated mild-to-moderate nerve damage. It might be possible, however, to redesign the cuffs to slowly reshape the nerves.

  16. Urokinase Plasminogen Receptor and the Fibrinolytic Complex Play a Role in Nerve Repair after Nerve Crush in Mice, and in Human Neuropathies

    PubMed Central

    Rivellini, Cristina; Dina, Giorgia; Porrello, Emanuela; Cerri, Federica; Scarlato, Marina; Domi, Teuta; Ungaro, Daniela; Carro, Ubaldo Del; Bolino, Alessandra; Quattrini, Angelo; Comi, Giancarlo; Previtali, Stefano C.

    2012-01-01

    Remodeling of extracellular matrix (ECM) is a critical step in peripheral nerve regeneration. In fact, in human neuropathies, endoneurial ECM enriched in fibrin and vitronectin associates with poor regeneration and worse clinical prognosis. Accordingly in animal models, modification of the fibrinolytic complex activity has profound effects on nerve regeneration: high fibrinolytic activity and low levels of fibrin correlate with better nerve regeneration. The urokinase plasminogen receptor (uPAR) is a major component of the fibrinolytic complex, and binding to urokinase plasminogen activator (uPA) promotes fibrinolysis and cell movement. uPAR is expressed in peripheral nerves, however, little is known on its potential function on nerve development and regeneration. Thus, we investigated uPAR null mice and observed that uPAR is dispensable for nerve development, whereas, loss of uPAR affects nerve regeneration. uPAR null mice showed reduced nerve repair after sciatic nerve crush. This was a consequence of reduced fibrinolytic activity and increased deposition of endoneurial fibrin and vitronectin. Exogenous fibrinolysis in uPAR null mice rescued nerve repair after sciatic nerve crush. Finally, we measured the fibrinolytic activity in sural nerve biopsies from patients with peripheral neuropathies. We showed that neuropathies with defective regeneration had reduced fibrinolytic activity. On the contrary, neuropathies with signs of active regeneration displayed higher fibrinolytic activity. Overall, our results suggest that enforced fibrinolysis may facilitate regeneration and outcome of peripheral neuropathies. PMID:22363796

  17. Biosynthesis and transport of gangliosides in peripheral nerve

    SciTech Connect

    Yates, A.J.; Tipnis, U.R.; Hofteig, J.H.; Warner, J.K.

    1984-01-01

    Radiolabelled glucosamine was injected into L-7 dorsal root ganglion (DRG) of rabbits. At several different times after injection DRG, lumbosacral trunks (LST) and sciatic nerves (SN) were removed and gangliosides extracted. Two and 3 weeks after injection the amounts of radioactivity in the ganglioside fractions of LST and SN were significantly higher than at days 1 and 2. The TCA soluble radioactivity decreased dramatically over the same time period. Colchicine prevented the appearance of radiolabelled lipid in LST and SN. From these experiments the authors conclude that some ganglioside is synthesized in the neuronal cell bodies of DRG and transported in the axons of the sciatic nerve. In another experiment the sciatic nerve was transected and ends separated to prevent regeneration. There was no difference in the amount of radiolabelled ganglioside that was isolated from DRG or LST of transected nerves compared with control nerves. The behavior of several potential acid soluble contaminants was studied in several steps used to isolate gangliosides. Of those studied only CMP-NeuAc could cause significant contamination of the final ganglioside preparation.

  18. Normal and sonographic anatomy of selected peripheral nerves. Part III: Peripheral nerves of the lower limb.

    PubMed

    Kowalska, Berta; Sudoł-Szopińska, Iwona

    2012-06-01

    The ultrasonographic examination is currently increasingly used in imaging peripheral nerves, serving to supplement the physical examination, electromyography and magnetic resonance imaging. As in the case of other USG imaging studies, the examination of peripheral nerves is non-invasive and well-tolerated by patients. The typical ultrasonographic picture of peripheral nerves as well as the examination technique have been discussed in part I of this article series, following the example of the median nerve. Part II of the series presented the normal anatomy and the technique for examining the peripheral nerves of the upper limb. This part of the article series focuses on the anatomy and technique for examining twelve normal peripheral nerves of the lower extremity: the iliohypogastric and ilioinguinal nerves, the lateral cutaneous nerve of the thigh, the pudendal, sciatic, tibial, sural, medial plantar, lateral plantar, common peroneal, deep peroneal and superficial peroneal nerves. It includes diagrams showing the proper positioning of the sonographic probe, plus USG images of the successively discussed nerves and their surrounding structures. The ultrasonographic appearance of the peripheral nerves in the lower limb is identical to the nerves in the upper limb. However, when imaging the lower extremity, convex probes are more often utilized, to capture deeply-seated nerves. The examination technique, similarly to that used in visualizing the nerves of upper extremity, consists of locating the nerve at a characteristic anatomic reference point and tracking it using the "elevator technique". All 3 parts of the article series should serve as an introduction to a discussion of peripheral nerve pathologies, which will be presented in subsequent issues of the "Journal of Ultrasonography".

  19. Proximal and distal changes in collagen content of peripheral nerve that follow transection and crush lesions.

    PubMed

    Eather, T F; Pollock, M; Myers, D B

    1986-05-01

    Collagen content of rat sciatic nerve was measured 10 weeks after either nerve transection or nerve crush. Nerve transection led to a significant increase in fascicular collagen in nerve segments 2.5 mm proximal and distal to the injury site. Remote from the transection, fascicular collagen was also significantly increased, this effect being most marked distally. Nerve crush by comparison resulted in only a small increase in fascicular collagen, significantly less than after transection. The greater amount of fascicular collagen far distal to the nerve injury could relate to a predominantly caudal endoneurial flow of inflammatory or growth factors. Differences in the amount of fascicular collagen formed after nerve transection compared with nerve crush are clearly due to factors other than axonal degeneration, and may relate to collagen synthesis by denervated Schwann cells or to the severity of the nerve injury.

  20. Dorsal root ganglion myeloid zinc finger protein 1 contributes to neuropathic pain after peripheral nerve trauma.

    PubMed

    Li, Zhisong; Gu, Xiyao; Sun, Linlin; Wu, Shaogen; Liang, Lingli; Cao, Jing; Lutz, Brianna Marie; Bekker, Alex; Zhang, Wei; Tao, Yuan-Xiang

    2015-04-01

    Peripheral nerve injury-induced changes in gene transcription and translation in primary sensory neurons of the dorsal root ganglion (DRG) are considered to contribute to neuropathic pain genesis. Transcription factors control gene expression. Peripheral nerve injury increases the expression of myeloid zinc finger protein 1 (MZF1), a transcription factor, and promotes its binding to the voltage-gated potassium 1.2 (Kv1.2) antisense (AS) RNA gene in the injured DRG. However, whether DRG MZF1 participates in neuropathic pain is still unknown. Here, we report that blocking the nerve injury-induced increase of DRG MZF1 through microinjection of MZF1 siRNA into the injured DRG attenuated the initiation and maintenance of mechanical, cold, and thermal pain hypersensitivities in rats with chronic constriction injury (CCI) of the sciatic nerve, without affecting locomotor functions and basal responses to acute mechanical, heat, and cold stimuli. Mimicking the nerve injury-induced increase of DRG MZF1 through microinjection of recombinant adeno-associated virus 5 expressing full-length MZF1 into the DRG produced significant mechanical, cold, and thermal pain hypersensitivities in naive rats. Mechanistically, MZF1 participated in CCI-induced reductions in Kv1.2 mRNA and protein and total Kv current and the CCI-induced increase in neuronal excitability through MZF1-triggered Kv1.2 AS RNA expression in the injured DRG neurons. MZF1 is likely an endogenous trigger of neuropathic pain and might serve as a potential target for preventing and treating this disorder. PMID:25630025

  1. Optical Biopsy of Peripheral Nerve Using Confocal Laser Endomicroscopy: A New Tool for Nerve Surgeons?

    PubMed Central

    Liao, Joseph C; Curtin, Catherine M

    2015-01-01

    Peripheral nerve injuries remain a challenge for reconstructive surgeons with many patients obtaining suboptimal results. Understanding the level of injury is imperative for successful repair. Current methods for distinguishing healthy from damaged nerve are time consuming and possess limited efficacy. Confocal laser endomicroscopy (CLE) is an emerging optical biopsy technology that enables dynamic, high resolution, sub-surface imaging of live tissue. Porcine sciatic nerve was either left undamaged or briefly clamped to simulate injury. Diluted fluorescein was applied topically to the nerve. CLE imaging was performed by direct contact of the probe with nerve tissue. Images representative of both damaged and undamaged nerve fibers were collected and compared to routine H&E histology. Optical biopsy of undamaged nerve revealed bands of longitudinal nerve fibers, distinct from surrounding adipose and connective tissue. When damaged, these bands appear truncated and terminate in blebs of opacity. H&E staining revealed similar features in damaged nerve fibers. These results prompt development of a protocol for imaging peripheral nerves intraoperatively. To this end, improving surgeons' ability to understand the level of injury through real-time imaging will allow for faster and more informed operative decisions than the current standard permits. PMID:26430636

  2. Chitosan-film enhanced chitosan nerve guides for long-distance regeneration of peripheral nerves.

    PubMed

    Meyer, Cora; Stenberg, Lena; Gonzalez-Perez, Francisco; Wrobel, Sandra; Ronchi, Giulia; Udina, Esther; Suganuma, Seigo; Geuna, Stefano; Navarro, Xavier; Dahlin, Lars B; Grothe, Claudia; Haastert-Talini, Kirsten

    2016-01-01

    Biosynthetic nerve grafts are developed in order to complement or replace autologous nerve grafts for peripheral nerve reconstruction. Artificial nerve guides currently approved for clinical use are not widely applied in reconstructive surgery as they still have limitations especially when it comes to critical distance repair. Here we report a comprehensive analysis of fine-tuned chitosan nerve guides (CNGs) enhanced by introduction of a longitudinal chitosan film to reconstruct critical length 15 mm sciatic nerve defects in adult healthy Wistar or diabetic Goto-Kakizaki rats. Short and long term investigations demonstrated that the CNGs enhanced by the guiding structure of the introduced chitosan film significantly improved functional and morphological results of nerve regeneration in comparison to simple hollow CNGs. Importantly, this was detectable both in healthy and in diabetic rats (short term) and the regeneration outcome almost reached the outcome after autologous nerve grafting (long term). Hollow CNGs provide properties likely leading to a wider clinical acceptance than other artificial nerve guides and their performance can be increased by simple introduction of a chitosan film with the same advantageous properties. Therefore, the chitosan film enhanced CNGs represent a new generation medical device for peripheral nerve reconstruction.

  3. Spinal cord response to laser treatment of injured peripheral nerve

    SciTech Connect

    Rochkind, S.; Vogler, I.; Barr-Nea, L. )

    1990-01-01

    The authors describe the changes occurring in the spinal cord of rats subjected to crush injury of the sciatic nerve followed by low-power laser irradiation of the injured nerve. Such laser treatment of the crushed peripheral nerve has been found to mitigate the degenerative changes in the corresponding neurons of the spinal cord and induce proliferation of neuroglia both in astrocytes and oligodendrocytes. This suggests a higher metabolism in neurons and a better ability for myelin production under the influence of laser treatment.

  4. Rare human nerve growth factor-β mutation reveals relationship between C-afferent density and acute pain evaluation.

    PubMed

    Perini, Irene; Tavakoli, Mitra; Marshall, Andrew; Minde, Jan; Morrison, India

    2016-08-01

    The rare nerve growth factor-β (NGFB) mutation R221W causes a selective loss of thinly myelinated fibers and especially unmyelinated C-fibers. Carriers of this mutation show altered pain sensation. A subset presents with arthropathic symptoms, with the homozygous most severely affected. The aim of the present study was to investigate the relationship between peripheral afferent loss and pain evaluation by performing a quantification of small-fiber density in the cornea of the carriers, relating density to pain evaluation measures. In vivo corneal confocal microscopy (CCM) was used to quantify C-fiber loss in the cornea of 19 R221W mutation carriers (3 homozygous) and 19 age-matched healthy control subjects. Pain evaluation data via the Situational Pain Questionnaire (SPQ) and the severity of neuropathy based on the Neuropathy Disability Score (NDS) were assessed. Homozygotes, heterozygotes, and control groups differed significantly in corneal C-nerve fiber density, with the homozygotes showing a significant afferent reduction. Importantly, peripheral C-fiber loss correlated negatively with pain evaluation, as revealed by SPQ scores. This study is the first to investigate the contribution of small-fiber density to the perceptual evaluation of pain. It demonstrates that the lower the peripheral small-fiber density, the lower the degree of reported pain intensity, indicating a functional relationship between small-fiber density and higher level pain experience. PMID:27146986

  5. Characterization of a neuropathic pain model: sciatic cryoneurolysis in the rat.

    PubMed

    DeLeo, J A; Coombs, D W; Willenbring, S; Colburn, R W; Fromm, C; Wagner, R; Twitchell, B B

    1994-01-01

    Cryoanalgesia, the technique of freezing peripheral nerves, is used clinically for the treatment of postoperative and chronic pain. Paradoxically, this same technique produces characteristics in a rat model suggestive of neuropathic pain. We have developed a peripheral neuropathy model by freezing the proximal sciatic nerve (sciatic cryoneurolysis, SCN) using a cryoprobe cooled to -60 degrees C in a 30/5/30 sec freeze-thaw-freeze sequence. Each freeze cycle produced a transient ice ball on the surface of the nerve. These studies provide behavioral evidence that SCN is a valid mononeuropathy animal model. All animals demonstrate some degree of autotomy following SCN. The average onset of autotomy occurs 4 days postoperatively and peaks in severity and incidence at 14 days. By examining the latency of responses to a noxious heat stimulus, we have shown there is no direct relationship between an hypoesthetic paw and autotomy, i.e., autotomy did not occur immediately after the freeze lesion when the limb was dysfunctional. Rather, autotomy peaked when sensation was returning to the affected limb. The transient time course of certain behaviors including hypoesthesia and possible return of limb sensation, autotomy, touch-evoked allodynia, foot edema and the presence of spontaneous nociceptive behaviors demonstrate a multiple phase nociceptive process. The temporary nature of these nociceptive behaviors is in sharp contrast to the prolonged bilateral mechanical allodynia evident when these behaviors subside. The surgical anesthetics used during the SCN procedure are shown to variably alter or suppress autotomy following SCN.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8159445

  6. Assessment of Neuroprotective Effects of Local Administration of 17- Beta- Estradiol on Peripheral Nerve Regeneration in Ovariectomized Female Rats

    PubMed Central

    Nobakhti-Afshar, Ahmadreza; Najafpour, Alireza; Mohammadi, Rahim; Zarei, Leila

    2016-01-01

    Objective: To assess the neuroprotective effects of local administration of 17- beta- estradiol on nerve regeneration. Methods: Sixty female Wistar rats were overiectomized and divided into four experimental groups (n = 15), randomly: In autograft group a segment of sciatic nerve was transected and re-implanted reversely. In sham-surgery group sciatic nerve was exposed and manipulated. In transected group left sciatic nerve was transected and stumps were fixed in adjacent muscle. In treatment group defect was bridged using a silicon conduit filled with 10 µL (0.1 mg/mL) 17- beta- estradiol. Each group was subdivided into four subgroups of five animals each and nerve fibers were studied in a 12-week period. Results: Behavioral, functional, biomechanical, electrophysiological and gastrocnemius muscle mass findings and morphometric indices confirmed faster recovery of regenerated axons in treatment group than in other groups (p<0.05). Immunohistochemical reactions to S-100 in treatment group were more positive than that in other groups. Conclusion: Local administration of 17-beta-estradiol improved functional recovery and morphometric indices of sciatic nerve. It could have clinical implications for the surgical management of patients after facial nerve transection. PMID:27540548

  7. Label-free photoacoustic microscopy of peripheral nerves

    PubMed Central

    Matthews, Thomas Paul; Zhang, Chi; Yao, Da-Kang; Maslov, Konstantin; Wang, Lihong V.

    2014-01-01

    Abstract. Peripheral neuropathy is a common neurological problem that affects millions of people worldwide. Diagnosis and treatment of this condition are often hindered by the difficulties in making objective, noninvasive measurements of nerve fibers. Photoacoustic microscopy (PAM) has the ability to obtain high resolution, specific images of peripheral nerves without exogenous contrast. We demonstrated the first proof-of-concept imaging of peripheral nerves using PAM. As validated by both standard histology and photoacoustic spectroscopy, the origin of photoacoustic signals is myelin, the primary source of lipids in the nerves. An extracted sciatic nerve sandwiched between two layers of chicken tissue was imaged by PAM to mimic the in vivo case. Ordered fibrous structures inside the nerve, caused by the bundles of myelin-coated axons, could be observed clearly. With further technical improvements, PAM can potentially be applied to monitor and diagnose peripheral neuropathies. PMID:24395587

  8. A Novel Model for Acute Peripheral Nerve Injury in the Horse and Evaluation of the Effect of Mesenchymal Stromal Cells Applied In Situ on Nerve Regeneration: A Preliminary Study

    PubMed Central

    Cruz Villagrán, Claudia; Schumacher, Jim; Donnell, Robert; Dhar, Madhu S.

    2016-01-01

    Transplantation of mesenchymal stromal cells (MSCs) to sites of experimentally created nerve injury in laboratory animals has shown promising results in restoring nerve function. This approach for nerve regeneration has not been reported in horses. In this study, we first evaluated the in vitro ability of equine bone marrow-derived MSCs (EBM-MSCs) to trans-differentiate into Schwann-like cells and subsequently tested the MSCs in vivo for their potential to regenerate a transected nerve after implantation. The EBM-MSCs from three equine donors were differentiated into SCLs for 7 days, in vitro, in the presence of specialized differentiation medium and evaluated for morphological characteristics, by using confocal microscopy, and for protein characteristics, by using selected Schwann cell markers (GFAP and S100b). The EBM-MSCs were then implanted into the fascia surrounding the ramus communicans of one fore limb of three healthy horses after a portion of this nerve was excised. The excised portion of the nerve was examined histologically at the time of transection, and stumps of the nerve were examined histologically at day 45 after transplantation. The EBM-MSCs from all donors demonstrated morphological and protein characteristics of those of Schwann cells 7 days after differentiation. Nerves implanted with EBM-MSCs after nerve transection did not show evidence of nerve regeneration at day 45. Examination of peripheral nerves collected 45 days after injury and stem cell treatment revealed no histological differences between nerves treated with MSCs and those treated with isotonic saline solution (controls). The optimal delivery of MSCs and the model suitable to study the efficacy of MSCs in nerve regeneration should be investigated. PMID:27695697

  9. A Novel Model for Acute Peripheral Nerve Injury in the Horse and Evaluation of the Effect of Mesenchymal Stromal Cells Applied In Situ on Nerve Regeneration: A Preliminary Study

    PubMed Central

    Cruz Villagrán, Claudia; Schumacher, Jim; Donnell, Robert; Dhar, Madhu S.

    2016-01-01

    Transplantation of mesenchymal stromal cells (MSCs) to sites of experimentally created nerve injury in laboratory animals has shown promising results in restoring nerve function. This approach for nerve regeneration has not been reported in horses. In this study, we first evaluated the in vitro ability of equine bone marrow-derived MSCs (EBM-MSCs) to trans-differentiate into Schwann-like cells and subsequently tested the MSCs in vivo for their potential to regenerate a transected nerve after implantation. The EBM-MSCs from three equine donors were differentiated into SCLs for 7 days, in vitro, in the presence of specialized differentiation medium and evaluated for morphological characteristics, by using confocal microscopy, and for protein characteristics, by using selected Schwann cell markers (GFAP and S100b). The EBM-MSCs were then implanted into the fascia surrounding the ramus communicans of one fore limb of three healthy horses after a portion of this nerve was excised. The excised portion of the nerve was examined histologically at the time of transection, and stumps of the nerve were examined histologically at day 45 after transplantation. The EBM-MSCs from all donors demonstrated morphological and protein characteristics of those of Schwann cells 7 days after differentiation. Nerves implanted with EBM-MSCs after nerve transection did not show evidence of nerve regeneration at day 45. Examination of peripheral nerves collected 45 days after injury and stem cell treatment revealed no histological differences between nerves treated with MSCs and those treated with isotonic saline solution (controls). The optimal delivery of MSCs and the model suitable to study the efficacy of MSCs in nerve regeneration should be investigated.

  10. Variable spatial magnetic field influences peripheral nerves regeneration in rats.

    PubMed

    Suszyński, Krzysztof; Marcol, Wiesław; Szajkowski, Sebastian; Pietrucha-Dutczak, Marita; Cieślar, Grzegorz; Sieroń, Aleksander; Lewin-Kowalik, Joanna

    2014-09-01

    Generator of spatial magnetic field is one of most recent achievements among the magnetostimulators. This apparatus allows to obtain the rotating magnetic field. This new method may be more effective than other widely used techniques of magnetostimulation and magnetotherapy. We investigated the influence of alternating, spatial magnetic field on the regeneration of the crushed rat sciatic nerves. Functional and morphological evaluations were used. After crush injury of the right sciatic nerve, Wistar C rats (n = 80) were randomly divided into four groups (control and three experimental). The experimental groups (A, B, C) were exposed (20 min/day, 5 d/week, 4 weeks) to alternating spatial magnetic field of three different intensities. Sciatic Functional Index (SFI) and tensometric assessments were performed every week after nerve crush. Forty-eight hours before the sacrificing of animals, DiI (1,1'-di-octadecyl-3,3,3',3'-tetramethyloindocarbocyanine perchlorate) was applied 5 mm distally to the crush site. Collected nerves and dorsal root ganglia (DRG) were subjected to histological and immunohistochemical staining. The survival rate of DRG neurons was estimated. Regrowth and myelination of the nerves was examined. The results of SFI and tensometric assessment showed improvement in all experimental groups as compared to control, with best outcome observed in group C, exposed to the strongest magnetic field. In addition, DRG survival rate and nerve regeneration intensity were significantly higher in the C group. Above results indicate that strong spatial alternating magnetic field exerts positive effect on peripheral nerve regeneration and its application could be taken under consideration in the therapy of injured peripheral nerves. PMID:23781984

  11. Medical countermeasure against respiratory toxicity and acute lung injury following inhalation exposure to chemical warfare nerve agent VX

    SciTech Connect

    Nambiar, Madhusoodana P.; Doctor, Bhupendra P.

    2007-03-15

    To develop therapeutics against lung injury and respiratory toxicity following nerve agent VX exposure, we evaluated the protective efficacy of a number of potential pulmonary therapeutics. Guinea pigs were exposed to 27.03 mg/m{sup 3} of VX or saline using a microinstillation inhalation exposure technique for 4 min and then the toxicity was assessed. Exposure to this dose of VX resulted in a 24-h survival rate of 52%. There was a significant increase in bronchoalveolar lavage (BAL) protein, total cell number, and cell death. Surprisingly, direct pulmonary treatment with surfactant, liquivent, N-acetylcysteine, dexamethasone, or anti-sense syk oligonucleotides 2 min post-exposure did not significantly increase the survival rate of VX-exposed guinea pigs. Further blocking the nostrils, airway, and bronchioles, VX-induced viscous mucous secretions were exacerbated by these aerosolized treatments. To overcome these events, we developed a strategy to protect the animals by treatment with atropine. Atropine inhibits muscarinic stimulation and markedly reduces the copious airway secretion following nerve agent exposure. Indeed, post-exposure treatment with atropine methyl bromide, which does not cross the blood-brain barrier, resulted in 100% survival of VX-exposed animals. Bronchoalveolar lavage from VX-exposed and atropine-treated animals exhibited lower protein levels, cell number, and cell death compared to VX-exposed controls, indicating less lung injury. When pulmonary therapeutics were combined with atropine, significant protection to VX-exposure was observed. These results indicate that combinations of pulmonary therapeutics with atropine or drugs that inhibit mucous secretion are important for the treatment of respiratory toxicity and lung injury following VX exposure.

  12. Medical countermeasure against respiratory toxicity and acute lung injury following inhalation exposure to chemical warfare nerve agent VX.

    PubMed

    Nambiar, Madhusoodana P; Gordon, Richard K; Rezk, Peter E; Katos, Alexander M; Wajda, Nikolai A; Moran, Theodore S; Steele, Keith E; Doctor, Bhupendra P; Sciuto, Alfred M

    2007-03-01

    To develop therapeutics against lung injury and respiratory toxicity following nerve agent VX exposure, we evaluated the protective efficacy of a number of potential pulmonary therapeutics. Guinea pigs were exposed to 27.03 mg/m(3) of VX or saline using a microinstillation inhalation exposure technique for 4 min and then the toxicity was assessed. Exposure to this dose of VX resulted in a 24-h survival rate of 52%. There was a significant increase in bronchoalveolar lavage (BAL) protein, total cell number, and cell death. Surprisingly, direct pulmonary treatment with surfactant, liquivent, N-acetylcysteine, dexamethasone, or anti-sense syk oligonucleotides 2 min post-exposure did not significantly increase the survival rate of VX-exposed guinea pigs. Further blocking the nostrils, airway, and bronchioles, VX-induced viscous mucous secretions were exacerbated by these aerosolized treatments. To overcome these events, we developed a strategy to protect the animals by treatment with atropine. Atropine inhibits muscarinic stimulation and markedly reduces the copious airway secretion following nerve agent exposure. Indeed, post-exposure treatment with atropine methyl bromide, which does not cross the blood-brain barrier, resulted in 100% survival of VX-exposed animals. Bronchoalveolar lavage from VX-exposed and atropine-treated animals exhibited lower protein levels, cell number, and cell death compared to VX-exposed controls, indicating less lung injury. When pulmonary therapeutics were combined with atropine, significant protection to VX-exposure was observed. These results indicate that combinations of pulmonary therapeutics with atropine or drugs that inhibit mucous secretion are important for the treatment of respiratory toxicity and lung injury following VX exposure.

  13. Choice of imaging modality in the diagnosis of sciatic hernia

    PubMed Central

    Labib, Peter L. Z.; Malik, Sohail N.

    2013-01-01

    Sciatic hernias are one of the rarest types of hernia and often pose diagnostic difficulty to clinicians. We report a case of an 80-year-old lady with a sciatic hernia who had a falsely negative computed tomography (CT) but was found to have a colonic hernia on ultrasonography. The authors recommend that for patients in which there is a high degree of clinical suspicion for a sciatic hernia and a negative CT, ultrasonography may be considered as a useful imaging modality to confirm the diagnosis. PMID:24968433

  14. Are Human Peripheral Nerves Sensitive to X-Ray Imaging?

    PubMed Central

    Scopel, Jonas Francisco; de Souza Queiroz, Luciano; O’Dowd, Francis Pierce; Júnior, Marcondes Cavalcante França; Nucci, Anamarli; Hönnicke, Marcelo Gonçalves

    2015-01-01

    Diagnostic imaging techniques play an important role in assessing the exact location, cause, and extent of a nerve lesion, thus allowing clinicians to diagnose and manage more effectively a variety of pathological conditions, such as entrapment syndromes, traumatic injuries, and space-occupying lesions. Ultrasound and nuclear magnetic resonance imaging are becoming useful methods for this purpose, but they still lack spatial resolution. In this regard, recent phase contrast x-ray imaging experiments of peripheral nerve allowed the visualization of each nerve fiber surrounded by its myelin sheath as clearly as optical microscopy. In the present study, we attempted to produce high-resolution x-ray phase contrast images of a human sciatic nerve by using synchrotron radiation propagation-based imaging. The images showed high contrast and high spatial resolution, allowing clear identification of each fascicle structure and surrounding connective tissue. The outstanding result is the detection of such structures by phase contrast x-ray tomography of a thick human sciatic nerve section. This may further enable the identification of diverse pathological patterns, such as Wallerian degeneration, hypertrophic neuropathy, inflammatory infiltration, leprosy neuropathy and amyloid deposits. To the best of our knowledge, this is the first successful phase contrast x-ray imaging experiment of a human peripheral nerve sample. Our long-term goal is to develop peripheral nerve imaging methods that could supersede biopsy procedures. PMID:25757086

  15. Aligned SF/P(LLA-CL)-blended nanofibers encapsulating nerve growth factor for peripheral nerve regeneration.

    PubMed

    Kuihua, Zhang; Chunyang, Wang; Cunyi, Fan; Xiumei, Mo

    2014-08-01

    Artificial nerve guidance conduits (NGCs) containing bioactive neurotrophic factors and topographical structure to biomimic native tissues are essential for efficient regeneration of nerve gaps. In this study, aligned SF/P(LLA-CL) nanofibers encapsulating nerve growth factor (NGF), which was stabilized by SF in core, were fabricated via a coaxial electrospinning technique. The controlled release of NGF from the nanofibers was evaluated using enzyme-linked immune sorbent assay (ELISA) and PC12 cell-based bioassay over a 60-day time period. The results demonstrated that NGF presented a sustained release and remained biological activity over 60 days. Nerve guidance conduits (NGCs) were fabricated by reeling the aligned SF/P(LLA-CL) nanofibrous scaffolds encapsulating NGF and then used as a bridge implanted across a 15-mm defect in the sciatic nerve of rats to promote nerve regeneration. The outcome in terms of regenerated nerve at 12 weeks was evaluated by a combination of electrophysiological assessment, histochemistry, and electron microscopy. All results clarified that the NGF-encapsulated-aligned SF/P(LLA-CL) NGCs promoted peripheral nerve regeneration significantly better than the aligned SF/P(LLA-CL) NGCs, suggesting that the released NGF from nanofibers could effectively promote the regeneration of peripheral nerve.

  16. Essential oil of Croton zehntneri and its main constituent anethole block excitability of rat peripheral nerve.

    PubMed

    da Silva-Alves, Kerly Shamyra; Ferreira-da-Silva, Francisco Walber; Coelho-de-Souza, Andrelina Noronha; Albuquerque, Aline Alice Cavalcante; do Vale, Otoni Cardoso; Leal-Cardoso, José Henrique

    2015-03-01

    Croton zehntneri is an aromatic plant native to Northeast Brazil and employed by local people to treat various diseases. The leaves of this plant have a rich content of essential oil. The essential oil of C. zehntneri samples, with anethole as the major constituent and anethole itself, have been reported to have several pharmacological activities such as antispasmodic, cardiovascular, and gastroprotective effects and inducing the blockade of neuromuscular transmission and antinociception. Since several works have demonstrated that essential oils and their constituents block cell excitability and in view of the multiple effects of C. zehntneri essential oil and anethole on biological tissues, we undertook this investigation aiming to characterize and compare the effects of this essential oil and its major constituent on nerve excitability. Sciatic nerves of Wistar rats were used. They were mounted in a moist chamber, and evoked compound action potentials were recorded. Nerves were exposed in vitro to the essential oil of C. zehntneri and anethole (0.1-1 mg/mL) up to 180 min, and alterations in excitability (rheobase and chronaxie) and conductibility (peak-to-peak amplitude and conduction velocity) parameters of the compound action potentials were evaluated. The essential oil of C. zehntneri and anethole blocked, in a concentration-dependent manner with similar pharmacological potencies (IC50: 0.32 ± 0.07 and 0.22 ± 0.11 mg/mL, respectively), rat sciatic nerve compound action potentials. Strength-duration curves for both agents were shifted upward and to the right compared to the control curve, and the rheobase and chronaxie were increased following essential oil and anethole exposure. The time courses of the essential oil of C. zehntneri and anethole effects on peak-to-peak amplitude of compound action potentials followed an exponential decay and reached a steady state. The essential oil of C. zehntneri and anethole caused a similar reduction in

  17. Essential oil of Croton zehntneri and its main constituent anethole block excitability of rat peripheral nerve.

    PubMed

    da Silva-Alves, Kerly Shamyra; Ferreira-da-Silva, Francisco Walber; Coelho-de-Souza, Andrelina Noronha; Albuquerque, Aline Alice Cavalcante; do Vale, Otoni Cardoso; Leal-Cardoso, José Henrique

    2015-03-01

    Croton zehntneri is an aromatic plant native to Northeast Brazil and employed by local people to treat various diseases. The leaves of this plant have a rich content of essential oil. The essential oil of C. zehntneri samples, with anethole as the major constituent and anethole itself, have been reported to have several pharmacological activities such as antispasmodic, cardiovascular, and gastroprotective effects and inducing the blockade of neuromuscular transmission and antinociception. Since several works have demonstrated that essential oils and their constituents block cell excitability and in view of the multiple effects of C. zehntneri essential oil and anethole on biological tissues, we undertook this investigation aiming to characterize and compare the effects of this essential oil and its major constituent on nerve excitability. Sciatic nerves of Wistar rats were used. They were mounted in a moist chamber, and evoked compound action potentials were recorded. Nerves were exposed in vitro to the essential oil of C. zehntneri and anethole (0.1-1 mg/mL) up to 180 min, and alterations in excitability (rheobase and chronaxie) and conductibility (peak-to-peak amplitude and conduction velocity) parameters of the compound action potentials were evaluated. The essential oil of C. zehntneri and anethole blocked, in a concentration-dependent manner with similar pharmacological potencies (IC50: 0.32 ± 0.07 and 0.22 ± 0.11 mg/mL, respectively), rat sciatic nerve compound action potentials. Strength-duration curves for both agents were shifted upward and to the right compared to the control curve, and the rheobase and chronaxie were increased following essential oil and anethole exposure. The time courses of the essential oil of C. zehntneri and anethole effects on peak-to-peak amplitude of compound action potentials followed an exponential decay and reached a steady state. The essential oil of C. zehntneri and anethole caused a similar reduction in

  18. Nerve biopsy

    MedlinePlus

    ... Loss of axon tissue Metabolic neuropathies Necrotizing vasculitis Sarcoidosis Risks Allergic reaction to the local anesthetic Discomfort ... Neurosarcoidosis Peripheral neuropathy Primary amyloidosis Radial nerve dysfunction Sarcoidosis Tibial nerve dysfunction Update Date 6/1/2015 ...

  19. Construction of nerve guide conduits from cellulose/soy protein composite membranes combined with Schwann cells and pyrroloquinoline quinone for the repair of peripheral nerve defect.

    PubMed

    Luo, Lihua; Gan, Li; Liu, Yongming; Tian, Weiqun; Tong, Zan; Wang, Xiong; Huselstein, Celine; Chen, Yun

    2015-02-20

    Regeneration and functional reconstruction of peripheral nerve defects remained a significant clinical challenge. Nerve guide conduits, with seed cells or neurotrophic factors (NTFs), had been widely used to improve the repair and regeneration of injured peripheral nerve. Pyrroloquinoline quinone (PQQ) was an antioxidant that can stimulate nerve growth factors (NGFs) synthesis and accelerate the Schwann cells (SCs) proliferation and growth. In present study, three kinds of nerve guide conduits were constructed: one from cellulose/SPI hollow tube (CSC), another from CSC combined with SCs (CSSC), and the third one from CSSC combined with PQQ (CSSPC), respectively. And then they were applied to bridge and repair the sciatic nerve defect in rats, using autograft as control. Effects of different nerve guide conduits on the nerve regeneration were comparatively evaluated by general analysis, sciatic function index (SFI) and histological analysis (HE and TEM). Newly-formed regenerative nerve fibers were observed and running through the transparent nerve guide conduits 12 weeks after surgery. SFI results indicated that the reconstruction of motor function in CSSPC group was better than that in CSSC and CSC groups. HE images from the cross-sections and longitudinal-sections of the harvested regenerative nerve indicated that regenerative nerve fibers had been formed and accompanied with new blood vessels and matrix materials in the conduits. TEM images also showed that lots of fresh myelinated and non-myelinated nerve fibers had been formed. Parts of vacuolar, swollen and abnormal axons occurred in CSC and CSSC groups, while the vacuolization and swell of axons was the least serious in CSSPC group. These results indicated that CSSPC group had the most ability to repair and reconstruct the nerve structure and functions due to the comprehensive contributions from hollow CSC tube, SCs and PQQ. As a result, the CSSPC may have the potential for the applications as nerve guide

  20. Local administration of icariin contributes to peripheral nerve regeneration and functional recovery.

    PubMed

    Chen, Bo; Niu, Su-Ping; Wang, Zhi-Yong; Wang, Zhen-Wei; Deng, Jiu-Xu; Zhang, Pei-Xun; Yin, Xiao-Feng; Han, Na; Kou, Yu-Hui; Jiang, Bao-Guo

    2015-01-01

    Our previous study showed that systemic administration of the traditional Chinese medicine Epimedium extract promotes peripheral nerve regeneration. Here, we sought to explore the therapeutic effects of local administration of icariin, a major component of Epimedium extract, on peripheral nerve regeneration. A poly(lactic-co-glycolic acid) biological conduit sleeve was used to bridge a 5 mm right sciatic nerve defect in rats, and physiological saline, nerve growth factor, icariin suspension, or nerve growth factor-releasing microsphere suspension was injected into the defect. Twelve weeks later, sciatic nerve conduction velocity and the number of myelinated fibers were notably greater in the rats treated with icariin suspension or nerve growth factor-releasing microspheres than those that had received nerve growth factor or physiological saline. The effects of icariin suspension were similar to those of nerve growth factor-releasing microspheres. These data suggest that icariin acts as a nerve growth factor-releasing agent, and indicate that local application of icariin after spinal injury can promote peripheral nerve regeneration. PMID:25788925

  1. Studies on nerve growth and repair

    SciTech Connect

    Ignatius, M.J.

    1985-01-01

    The transition of nerve cell from a dividing undifferentiated cell to a morphologically differentiated nondividing cell was studied. Pheochromocytoma (PC12) cells respond to nerve growth factor (NGF) by extending electrically excitable neurites. Yet by labeling these cells with /sup 3/H-thymidine and examining them autoradiographically, evidence for continued DNA replication in neurite bearing neurons was found. NGF receptors of two classes are expressed on PC12 cells and other NGF dependent neurons. By labeling differentiated PC12s in culture with /sup 125/I-NGF and examining them autoradiographically both receptor classes were found evenly distributed on the growth cones, neurites and cell bodies. Cytoskeletal associated receptors were found in these areas as well. The purification and identification of a soluble, extracellular protein of 37,000 molecular weight whose synthesis and accumulation is increased after injury of a rat sciatic nerve is described.

  2. Polymer scaffolds with preferential parallel grooves enhance nerve regeneration.

    PubMed

    Mobasseri, Atefeh; Faroni, Alessandro; Minogue, Ben M; Downes, Sandra; Terenghi, Giorgio; Reid, Adam J

    2015-03-01

    We have modified the surface topography of poly ɛ-caprolactone (PCL) and polylactic acid (PLA) blended films to improve cell proliferation and to guide the regeneration of peripheral nerves. Films with differing shaped grooves were made using patterned silicon templates, sloped walls (SL), V-shaped (V), and square-shaped (SQ), and compared with nongrooved surfaces with micropits. The solvent cast films were tested in vitro using adult adipose-derived stem cells differentiated to Schwann cell-like cells. Cell attachment, proliferation, and cell orientation were all improved on the grooved surfaces, with SL grooves giving the best results. We present in vivo data on Sprague-Dawley rat sciatic nerve injury with a 10-mm gap, evaluating nerve regeneration at 3 weeks across a polymer nerve conduit modified with intraluminal grooves (SL, V, and SQ) and differing wall thicknesses (70, 100, 120, and 210 μm). The SL-grooved nerve conduit showed a significant improvement over the other topographical-shaped grooves, while increasing the conduit wall thickness saw no positive effect on the biological response of the regenerating nerve. Furthermore, the preferred SL-grooved conduit (C) with 70 μm wall thickness was compared with the current clinical gold standard of autologous nerve graft (Ag) in the rat 10-mm sciatic nerve gap model. At 3 weeks postsurgery, all nerve gaps across both groups were bridged with regenerated nerve fibers. At 16 weeks, features of regenerated axons were comparable between the autograft (Ag) and conduit (C) groups. End organ assessments of muscle weight, electromyography, and skin reinnervation were also similar between the groups. The comparable experimental outcome between conduit and autograft, suggests that the PCL/PLA conduit with inner lumen microstructured grooves could be used as a potential alternative treatment for peripheral nerve repair. PMID:25435096

  3. Polymer Scaffolds with Preferential Parallel Grooves Enhance Nerve Regeneration

    PubMed Central

    Mobasseri, Atefeh; Faroni, Alessandro; Minogue, Ben M.; Downes, Sandra; Reid, Adam J.

    2015-01-01

    We have modified the surface topography of poly ɛ-caprolactone (PCL) and polylactic acid (PLA) blended films to improve cell proliferation and to guide the regeneration of peripheral nerves. Films with differing shaped grooves were made using patterned silicon templates, sloped walls (SL), V-shaped (V), and square-shaped (SQ), and compared with nongrooved surfaces with micropits. The solvent cast films were tested in vitro using adult adipose-derived stem cells differentiated to Schwann cell-like cells. Cell attachment, proliferation, and cell orientation were all improved on the grooved surfaces, with SL grooves giving the best results. We present in vivo data on Sprague-Dawley rat sciatic nerve injury with a 10-mm gap, evaluating nerve regeneration at 3 weeks across a polymer nerve conduit modified with intraluminal grooves (SL, V, and SQ) and differing wall thicknesses (70, 100, 120, and 210 μm). The SL-grooved nerve conduit showed a significant improvement over the other topographical-shaped grooves, while increasing the conduit wall thickness saw no positive effect on the biological response of the regenerating nerve. Furthermore, the preferred SL-grooved conduit (C) with 70 μm wall thickness was compared with the current clinical gold standard of autologous nerve graft (Ag) in the rat 10-mm sciatic nerve gap model. At 3 weeks postsurgery, all nerve gaps across both groups were bridged with regenerated nerve fibers. At 16 weeks, features of regenerated axons were comparable between the autograft (Ag) and conduit (C) groups. End organ assessments of muscle weight, electromyography, and skin reinnervation were also similar between the groups. The comparable experimental outcome between conduit and autograft, suggests that the PCL/PLA conduit with inner lumen microstructured grooves could be used as a potential alternative treatment for peripheral nerve repair. PMID:25435096

  4. Development and Application of Acute Exposure Guideline Levels (AEGLs) for Chemical Warfare Nerve and Sulfur Mustard Agents.

    SciTech Connect

    Watson, Annetta Paule; Opresko, Dennis M; Young, Robert A; Hauschild, Veronique

    2006-01-01

    Acute exposure guideline levels (AEGLs) have been developed for the chemical warfare agents GB, GA, GD, GF, VX, and sulfur mustard. These AEGLs were approved by the National Advisory Committee for Acute Exposure Guideline Levels for Hazardous Substances after Federal Register publication and comment, and judged as scientifically valid by the National Research Council Committee on Toxicology Subcommittee on AEGLs. AEGLs represent general public exposure limits for durations ranging from 10 min to 8 h, and for three levels of severity (AEGL-1, AEGL-2, AEGL-3). Mild effects are possible at concentrations greater than AEGL-1, while life-threatening effects are expected at concentrations greater than AEGL-3. AEGLs can be applied to various civilian and national defense purposes, including evacuation and shelter-in-place protocols, reentry levels, protective clothing specifications, and analytical monitoring requirements. This report documents development and derivation of AEGL values for six key chemical warfare agents, and makes recommendations for their application to various potential exposure scenarios.

  5. A Novel Internal Fixator Device for Peripheral Nerve Regeneration

    PubMed Central

    Chuang, Ting-Hsien; Wilson, Robin E.; Love, James M.; Fisher, John P.

    2013-01-01

    Recovery from peripheral nerve damage, especially for a transected nerve, is rarely complete, resulting in impaired motor function, sensory loss, and chronic pain with inappropriate autonomic responses that seriously impair quality of life. In consequence, strategies for enhancing peripheral nerve repair are of high clinical importance. Tension is a key determinant of neuronal growth and function. In vitro and in vivo experiments have shown that moderate levels of imposed tension (strain) can encourage axonal outgrowth; however, few strategies of peripheral nerve repair emphasize the mechanical environment of the injured nerve. Toward the development of more effective nerve regeneration strategies, we demonstrate the design, fabrication, and implementation of a novel, modular nerve-lengthening device, which allows the imposition of moderate tensile loads in parallel with existing scaffold-based tissue engineering strategies for nerve repair. This concept would enable nerve regeneration in two superposed regimes of nerve extension—traditional extension through axonal outgrowth into a scaffold and extension in intact regions of the proximal nerve, such as that occurring during growth or limb-lengthening. Self-sizing silicone nerve cuffs were fabricated to grip nerve stumps without slippage, and nerves were deformed by actuating a telescoping internal fixator. Poly(lactic co-glycolic) acid (PLGA) constructs mounted on the telescoping rods were apposed to the nerve stumps to guide axonal outgrowth. Neuronal cells were exposed to PLGA using direct contact and extract methods, and they exhibited no signs of cytotoxic effects in terms of cell morphology and viability. We confirmed the feasibility of implanting and actuating our device within a sciatic nerve gap and observed axonal outgrowth following device implantation. The successful fabrication and implementation of our device provides a novel method for examining mechanical influences on nerve regeneration. PMID

  6. Peripheral nerve regeneration using composite poly(lactic acid-caprolactone)/nerve growth factor conduits prepared by coaxial electrospinning.

    PubMed

    Liu, Jun-Jian; Wang, Chun-Yang; Wang, Jian-Guang; Ruan, Hong-Jiang; Fan, Cun-Yi

    2011-01-01

    Many neurotrophic factors have been shown to promote neurite outgrowth by improving the microenvironment that is required for nerve regeneration. However, the delivery of these bioactive agents to the nerve injury site, as well as effective and local release, remains a challenging problem. We have developed a novel composite nerve conduit comprised of poly(lactic acid-caprolactone) (P(LLA-CL)) and nerve growth factor (NGF). This was developed from core-shell structured biodegradable nanofibers, which were fabricated by coaxial electrospinning of P(LLA-CL) for the shell and bovine serum albumin (BSA) or BSA/NGF for the core. In rats, gaps of 10-mm long sciatic nerves were bridged using an autograft, an empty P(LLA-CL) conduit, a NGF injection P(LLA-CL) conduit, a P(LLA-CL)/NGF composite conduit, respectively. Regenerated nerve fibers were harvested and morphological and functional evaluation of nerve regeneration was performed at 12 weeks postsurgery. Although partial biodegradation and small cracks in the conduits were observed, the conduit outlines remained intact for 12 weeks after surgery. Based on functional and histological observations, the number and arrangement of regenerated nerve fibers, myelination, and nerve function reconstruction was similar in the P(LLA-CL)/NGF conduit group to that of the nerve autograft group (p > 0.05), but was significantly greater to the empty P(LLA-CL) and injection NGF P(LLA-CL) conduit groups (both p < 0.05). Therefore, the composite P(LLA-CL)/NGF conduit, which exhibited favorable mechanical properties and biocompatibility, could effectively promote sciatic nerve regeneration in rats.

  7. Non-invasive vagus nerve stimulation for PREVention and Acute treatment of chronic cluster headache (PREVA): A randomised controlled study

    PubMed Central

    Diener, Hans-Christoph; Silver, Nicholas; Magis, Delphine; Reuter, Uwe; Andersson, Annelie; Liebler, Eric J; Straube, Andreas

    2015-01-01

    Background Chronic cluster headache (CH) is a debilitating disorder for which few well-controlled studies demonstrate effectiveness of available therapies. Non-invasive vagus nerve stimulation (nVNS) was examined as adjunctive prophylactic treatment of chronic CH. Methods PREVA was a prospective, open-label, randomised study that compared adjunctive prophylactic nVNS (n = 48) with standard of care (SoC) alone (control (n = 49)). A two-week baseline phase was followed by a four-week randomised phase (SoC plus nVNS vs control) and a four-week extension phase (SoC plus nVNS). The primary end point was the reduction in the mean number of CH attacks per week. Response rate, abortive medication use and safety/tolerability were also assessed. Results During the randomised phase, individuals in the intent-to-treat population treated with SoC plus nVNS (n = 45) had a significantly greater reduction in the number of attacks per week vs controls (n = 48) (−5.9 vs −2.1, respectively) for a mean therapeutic gain of 3.9 fewer attacks per week (95% CI: 0.5, 7.2; p = 0.02). Higher ≥50% response rates were also observed with SoC plus nVNS (40% (18/45)) vs controls (8.3% (4/48); p < 0.001). No serious treatment-related adverse events occurred. Conclusion Adjunctive prophylactic nVNS is a well-tolerated novel treatment for chronic CH, offering clinical benefits beyond those with SoC. PMID:26391457

  8. A Prospective Observational Cohort Study on Orthopaedic and Anaesthetic Registrars Performing Femoral Nerve Block on Patients with an Acute Hip Fracture

    PubMed Central

    Thelaus, Åsa; Pettersson, Tobias; Gordon, Max

    2016-01-01

    We investigated if a femoral nerve block (FNB) for patients with a proximal femoral fracture (PFF) and administered by an orthopaedic registrar (OR) instead of an anaesthesiology registrar (AR) lowers the lead time to block and reduces the total amount of rescue analgesics during the preoperative phase. 205 patients were included in a prospective observational cohort study. The main outcome variable was rescue analgesics as total intravenous morphine prior to surgery. All results were adjusted for confounding using age, sex, cognitive dysfunction, and ASA classification. The OR group (n = 135) was over 2 hours faster in performing the block compared to the AR group (n = 70) but was nonetheless correlated with an increased amount of rescue analgesics during the study, 2.4 mg morphine (95% CI 0.0–4.9) more compared to the AR group. We found no difference between the groups in the risk of adverse events. We conclude that, for patients with an acute PFF and with morphine consumption as end point, how soon from arrival to hospital the patients receive a FNB is of lesser importance than who is administering it. Based on our results we recommend that emergency hospitals should have routines for anaesthesiologists performing FNB on this frail patient group. PMID:27704039

  9. Amniotic mesenchymal stem cells display neurovascular tropism and aid in the recovery of injured peripheral nerves.

    PubMed

    Li, YongNan; Guo, Longzhe; Ahn, Hyun Sook; Kim, Moo Hyun; Kim, Sung-Whan

    2014-06-01

    Recently, we reported that human amniotic membrane-derived mesenchymal stem cells (AMMs) possess great angiogenic potential. In this study, we determined whether local injection of AMMs ameliorates peripheral neuropathy. AMMs were transplanted into injured sciatic nerves. AMM injection promoted significant recovery of motor nerve conduction velocity and voltage amplitude compared to human adipose-derived mesenchymal stem cells. AMM implantation also augmented blood perfusion and increased intraneural vascularity. Whole-mount fluorescent imaging analysis demonstrated that AMMs exhibited higher engraftment and endothelial incorporation abilities in the sciatic nerve. In addition, the higher expression of pro-angiogenic factors was detected in AMMs injected into the peripheral nerve. Therefore, these data provide novel therapeutic and mechanistic insights into stem cell biology, and AMM transplantation may represent an alternative therapeutic option for treating peripheral neuropathy.

  10. A prospective study of acute idiopathic neuropathy. III. Immunological studies.

    PubMed Central

    Winer, J B; Gray, I A; Gregson, N A; Hughes, R A; Leibowitz, S; Shepherd, P; Taylor, W A; Yewdall, V

    1988-01-01

    The immune responses of 100 patients who presented with an acute idiopathic neuropathy were compared with those of age and sex matched controls. Blood lymphocytes and their subsets were counted with a fluorescent activated cell sorter. CD8+ (putative suppressor) lymphocytes were significantly reduced in the first week of the disease but total lymphocytes, total T and CD4+ (putative helper) cells were not altered. This reduction depended on the nature of the preceding infection. Serum complement C3 and C4 concentrations remained normal and immune complexes were rarely detected with a C1q binding assay. Complement-fixing antibodies to human peripheral nerve antigens were discovered in the serum of 7% of patients but only 1% of controls. Complement-fixing antibodies to galactocerebroside were not discovered in any sera. Enzyme-linked immunoassays detected increased antibody responses to galactocerebroside but none at all to human P2 myelin protein in the patient sera. Forty microliter of serum from five patients injected into the sciatic nerves of rats did not induce significantly more demyelination than the serum from control patients. It is concluded that auto-immune responses can only be detected by these techniques in a small minority of patients with acute idiopathic neuropathy. PMID:2969956

  11. Handcrafted multilayer PDMS microchannel scaffolds for peripheral nerve regeneration.

    PubMed

    Hossain, Ridwan; Kim, Bongkyun; Pankratz, Rachel; Ajam, Ali; Park, Sungreol; Biswal, Sibani L; Choi, Yoonsu

    2015-12-01

    Injuries that result in the loss of limb functionality may be caused by the severing of the peripheral nerves within the affected limb. Several bioengineered peripheral nerve scaffolds have been developed in order to provide the physical support and topographical guidance necessary for the naturally disorganized axon outgrowth to reattach to distal nerve stumps as an alternative to other procedures, like nerve grafting. PDMS has been chosen for the base material of the scaffolds due to its biocompatibility, flexibility, transparency, and well-developed fabrication techniques. The process of observing the axon outgrowth across the nerve gaps with PDMS scaffolds has been challenging due to the limited number and fineness of longitudinal sections that can be extracted from harvested nerve tissue samples after implantation. To address this, multilayer microchannel scaffolds were developed with the object of providing more refined longitudinal observation of axon outgrowth by longitudinally 'sectioning' the device during fabrication, removing the need for much of the sample preparation process. This device was then implanted into the sciatic nerves of Lewis rats, and then harvested after two and four weeks to analyze the difference in nerve regeneration between two different time periods. The present layer by layer structure, which is separable after nerve regeneration and is treated as an individual layer during the histology process, provides the details of biological events during axonal regeneration. Confocal microscopic imaging showed the details of peripheral nerve regeneration including nerve branches and growth cones observable from within the microchannels of the multilayer PDMS microchannel scaffolds.

  12. A Biosynthetic Nerve Guide Conduit Based on Silk/SWNT/Fibronectin Nanocomposite for Peripheral Nerve Regeneration

    PubMed Central

    Mottaghitalab, Fatemeh; Farokhi, Mehdi; Zaminy, Arash; Kokabi, Mehrdad; Soleimani, Masoud; Mirahmadi, Fereshteh

    2013-01-01

    As a contribution to the functionality of nerve guide conduits (NGCs) in nerve tissue engineering, here we report a conduit processing technique through introduction and evaluation of topographical, physical and chemical cues. Porous structure of NGCs based on freeze-dried silk/single walled carbon nanotubes (SF/SWNTs) has shown a uniform chemical and physical structure with suitable electrical conductivity. Moreover, fibronectin (FN) containing nanofibers within the structure of SF/SWNT conduits produced through electrospinning process have shown aligned fashion with appropriate porosity and diameter. Moreover, fibronectin remained its bioactivity and influenced the adhesion and growth of U373 cell lines. The conduits were then implanted to 10 mm left sciatic nerve defects in rats. The histological assessment has shown that nerve regeneration has taken places in proximal region of implanted nerve after 5 weeks following surgery. Furthermore, nerve conduction velocities (NCV) and more myelinated axons were observed in SF/SWNT and SF/SWNT/FN groups after 5 weeks post implantation, indicating a functional recovery for the injured nerves. With immunohistochemistry, the higher S-100 expression of Schwann cells in SF/SWNT/FN conduits in comparison to other groups was confirmed. In conclusion, an oriented conduit of biocompatible SF/SWNT/FN has been fabricated with acceptable structure that is particularly applicable in nerve grafts. PMID:24098649

  13. Adjuvant neurotrophic factors in peripheral nerve repair with chondroitin sulfate proteoglycan-reduced acellular nerve allografts

    PubMed Central

    Boyer, Richard B.; Sexton, Kevin W.; Rodriguez-Feo, Charles L.; Nookala, Ratnam; Pollins, Alonda C.; Cardwell, Nancy L.; Tisdale, Keonna Y.; Nanney, Lillian B.; Shack, R. Bruce; Thayer, Wesley P.

    2014-01-01

    Background Acellular nerve allografts are now standard tools in peripheral nerve repair due to decreased donor site morbidity and operative time savings. Preparation of nerve allografts involves several steps of decellularization and modification of extracellular matrix to remove chondroitin sulfate proteoglycans (CSPGs), which have been shown to inhibit neurite outgrowth through a poorly understood mechanism involving RhoA and ECM-integrin interactions. Chondroitinase ABC (ChABC) is an enzyme that degrades CSPG molecules and has been shown to promote neurite outgrowth following injury of the central and peripheral nervous systems. Variable results following chondroitinase ABC treatment make it difficult to predict the effects of this drug in human nerve allografts, especially in the presence of native extracellular signaling molecules. Several studies have shown cross-talk between neurotrophic factor and CSPG signaling pathways, but their interaction remains poorly understood. In this study, we examined the adjuvant effects of nerve growth factor (NGF) and glial cell line-derived neurotrophic factor (GDNF) on neurite outgrowth post-injury in CSPG-reduced substrates and acellular nerve allografts. Materials and Methods E12 chicken DRG explants were cultured in medium containing ChABC, ChABC + NGF, ChABC + GDNF or control media. Explants were imaged at 3 d and neurite outgrowths measured. The rat sciatic nerve injury model involved a 1-cm sciatic nerve gap that was microsurgically repaired with ChABC pre-treated acellular nerve allografts. Prior to implantation, nerve allografts were incubated in NGF, GDNF or sterile water. Nerve histology was evaluated at 5d and 8wk post-injury. Results The addition of GDNF in vitro produced significant increase in sensory neurite length at 3 d compared to ChABC alone (P < 0.01), while NGF was not significantly different from control. In vivo adjuvant NGF produced increases in total myelinated axon count (P < 0.005) and motor axon

  14. A comparison of the performance of mono- and bi-component electrospun conduits in a rat sciatic model

    PubMed Central

    Cirillo, Valentina; Clements, Basak A.; Guarino, Vincenzo; Bushman, Jared; Kohn, Joachim; Ambrosio, Luigi

    2015-01-01

    Synthetic nerve conduits represent a promising strategy to enhance functional recovery in peripheral nerve injury repair. However, the efficiency of synthetic nerve conduits is often compromised by the lack of molecular factors to create an enriched microenvironment for nerve regeneration. Here, we investigate the in vivo response of mono (MC) and bi-component (BC) fibrous conduits obtained by processing via electrospinning poly(ε-caprolactone) (PCL) and gelatin solutions. In vitro studies demonstrate that the inclusion of gelatin leads to uniform electrospun fiber size and positively influences the response of Dorsal Root Ganglia (DRGs) neurons as confirmed by the preferential extensions of neurites from DRG bodies. This behavior can be attributed to gelatin as a bioactive cue for the cultured DRG and to the reduced fibers size. However, in vivo studies in rat sciatic nerve defect model show an opposite response: MC conduits stimulate superior nerve regeneration than gelatin containing PCL conduits as confirmed by electrophysiology, muscle weight and histology. The G-ratio, 0.71 ± 0.07 for MC and 0.66 ± 0.05 for autograft, is close to 0.6, the value measured in healthy nerves. In contrast, BC implants elicited a strong host response and infiltrating tissue occluded the conduits preventing the formation of myelinated axons. Therefore, although gelatin promotes in vitro nerve regeneration, we conclude that bi-component electrospun conduits are not satisfactory in vivo due to intrinsic limits to their mechanical performance and degradation kinetics, which are essential to peripheral nerve regeneration in vivo. PMID:25085857

  15. Multifunctional Silk Nerve Guides for Axon Outgrowth

    NASA Astrophysics Data System (ADS)

    Tupaj, Marie C.

    Peripheral nerve regeneration is a critical issue as 2.8% of trauma patients present with this type of injury, estimating a total of 200,000 nerve repair procedures yearly in the United States. While the peripheral nervous system exhibits slow regeneration, at a rate of 0.5 mm -- 9 mm/day following trauma, this regenerative ability is only possible under certain conditions. Clinical repairs have changed slightly in the last 30 years and standard methods of treatment include suturing damaged nerve ends, allografting, and autografting, with the autograft the gold standard of these approaches. Unfortunately, the use of autografts requires a second surgery and there is a shortage of nerves available for grafting. Allografts are a second option however allografts have lower success rates and are accompanied by the need of immunosuppressant drugs. Recently there has been a focus on developing nerve guides as an "off the shelf" approach. Although some natural and synthetic guidance channels have been approved by the FDA, these nerve guides are unfunctionalized and repair only short gaps, less than 3 cm in length. The goal of this project was to identify strategies for functionalizing peripheral nerve conduits for the outgrowth of neuron axons in vitro . To accomplish this, two strategies (bioelectrical and biophysical) were indentified for increasing axon outgrowth and promoting axon guidance. Bioelectrical strategies exploited electrical stimulation for increasing neurite outgrowth. Biophysical strategies tested a range of surface topographies for axon guidance. Novel methods were developed for integrating electrical and biophysical strategies into silk films in 2D. Finally, a functionalized nerve conduit system was developed that integrated all strategies for the purpose of attaching, elongating, and guiding nervous tissue in vitro. Future directions of this work include silk conduit translation into a rat sciatic nerve model in vivo for the purpose of repairing long

  16. A bioengineered peripheral nerve construct using aligned peptide amphiphile nanofibers

    PubMed Central

    Yalom, Anisa; Berns, Eric J.; Stephanopoulos, Nicholas; McClendon, Mark T.; Segovia, Luis A.; Spigelman, Igor; Stupp, Samuel I.; Jarrahy, Reza

    2014-01-01

    Peripheral nerve injuries can result in lifelong disability. Primary coaptation is the treatment of choice when the gap between transected nerve ends is short. Long nerve gaps seen in more complex injuries often require autologous nerve grafts or nerve conduits implemented into the repair. Nerve grafts, however, cause morbidity and functional loss at donor sites, which are limited in number. Nerve conduits, in turn, lack an internal scaffold to support and guide axonal regeneration, resulting in decreased efficacy over longer nerve gap lengths. By comparison, peptide amphiphiles (PAs) are molecules that can self-assemble into nanofibers, which can be aligned to mimic the native architecture of peripheral nerve. As such, they represent a potential substrate for use in a bioengineered nerve graft substitute. To examine this, we cultured Schwann cells with bioactive PAs (RGDS-PA, IKVAV-PA) to determine their ability to attach to and proliferate within the biomaterial. Next, we devised a PA construct for use in a peripheral nerve critical sized defect model. Rat sciatic nerve defects were created and reconstructed with autologous nerve, PLGA conduits filled with various forms of aligned PAs, or left unrepaired. Motor and sensory recovery were determined and compared among groups. Our results demonstrate that Schwann cells are able to adhere to and proliferate in aligned PA gels, with greater efficacy in bioactive PAs compared to the backbone-PA alone. In vivo testing revealed recovery of motor and sensory function in animals treated with conduit/PA constructs comparable to animals treated with autologous nerve grafts. Functional recovery in conduit/PA and autologous graft groups was significantly faster than in animals treated with empty PLGA conduits. Histological examinations also demonstrated increased axonal and Schwann cell regeneration within the reconstructed nerve gap in animals treated with conduit/PA constructs. These results indicate that PA nanofibers may

  17. Neuroprotective Effect of Natural Products on Peripheral Nerve Degeneration: A Systematic Review.

    PubMed

    Araújo-Filho, Heitor G; Quintans-Júnior, Lucindo J; Barreto, André S; Almeida, Jackson R G S; Barreto, Rosana S S; Quintans, Jullyana S S

    2016-04-01

    Peripheral nerve injury (PNI) is a serious public health problem that is linked with motor, sensory and autonomic deficits. Given the fact that this type of disorder leads to a decreased quality of life in most patients and adherence of available drugs is limited and have adverse effects, we investigated the efficacy of natural products in a PNI model. The search terms plants, medicinal, nerve regeneration, nerve crush, sciatic nerve as well as MeSH terms or free-text words were used to retrieve English language articles in PubMed, Scopus, Web of Science and LILACS published until July 2015. After sciatic nerve crush, natural products have improved significantly motor performance, sensory function and electrical conductance measured over weeks. Among the pharmacological targets suggested by the action of natural products, there were citations on the activation of the antiapoptotic signaling pathway, modulation in the expression of pro-inflammatory cytokines and neurotrophic factors. The systematic review provides scientific evidence that natural products are pharmacologically effective in the treatment of PNI such as sciatic nerve crush.

  18. 2,5-hexanedione altered the degradation of low-molecular-weight neurofilament in rat nerve tissues.

    PubMed

    Song, Fuyong; Zhang, Qingguo; Kou, Ruirui; Zou, Chaoshuang; Gao, Yuan; Xie, Keqin

    2012-12-01

    Occupational exposure to n-hexane produces a central-peripheral distal axonopathy, which is characterized by giant axonal swellings filled with neurofilaments (NFs). To investigate the change of NFs degradation and their possible role in n-hexane neuropathy, adult male Wistar rats were administered intraperitoneally at a dosage of 400 mg/kg/day 2,5-hexanedione (2,5-HD) for 4 weeks. The time course of low-molecular-weight neurofilament (NF-L) degradation and autophagy-related protein in rat sciatic nerves and spinal cords was determined by Western blotting. The results demonstrated that the administration of 2,5-HD inhibited NF-L degradation to an undetectable level in sciatic nerves. Furthermore, a significant reduction of NF-L degradation in spinal cords was observed in the early stage of 2,5-HD exposure. In the meantime, 2,5-HD significantly decreased the level of Beclin-1, a key autophagy-regulated protein in sciatic nerves of rats while increased the level of P62, a selective substrate of autophagy degrading pathway, which indicated a dysfunctional autophagy in rat nerve tissues. Collectively, our findings suggested that the inhibition of autophagy by 2,5-HD might be responsible for the reduction of NF-L degradation in rat sciatic nerves, and involved in the pathogenesis of 2,5-HD-induced axonopathy.

  19. Endothelial dysfunction and increased responses to renal nerve stimulation in rat kidneys during rhabdomyolysis-induced acute renal failure: role of hydroxyl radical.

    PubMed

    Cil, Onur; Ertunc, Mert; Gucer, Kadri Safak; Ozaltin, Fatih; Iskit, Alper Bektas; Onur, Rustu

    2012-01-01

    Rhabdomyolysis is an important cause of acute renal failure (ARF) and renal vasoconstriction is the main mechanism in the pathogenesis of ARF. Lipid peroxidation due to hydroxyl radical (.OH) formation and redox cycling of myoglobin also have a role. We investigated the disturbance in renal vascular reactivity to reveal the mechanisms leading to ARF. Female Wistar rats (n = 7) were injected with glycerol (10 mL/kg, 50% in saline) intramuscularly to induce rhabdomyolysis, and then the kidneys were isolated and perfused. We investigated acetylcholine (ACh)-induced endothelium-dependent and papaverine (PAP)-induced endothelium-independent vasodilation responses and renal nerve stimulation (RNS)-induced vasoconstrictions. These were also investigated both in rats which received either .OH scavenger, dimethylthiourea (DMTU: 500 mg/kg before glycerol injection and 125 mg/kg 8 h after glycerol injection, n = 7), or myoglobin redox cycling inhibitor, acetaminophen (ApAP: 100 mg/kg 2 h before glycerol injection and 100 mg/kg each 4 h, and 22 h after glycerol injection, n = 7). ACh-induced responses in glycerol group were decreased (p < 0.001), but PAP-induced vasodilation did not change. RNS-induced vasoconstriction in all kidneys was greater (p < 0.001) in glycerol group. DMTU restored both endothelium-dependent vasodilation and RNS-induced vasoconstriction. ApAP had no effect on vascular responses. Both DMTU and ApAP exerted a partial protective effect in renal histology without restoring serum creatinine and blood urea nitrogen (BUN) levels or creatinine clearance. This study showed that endothelial dysfunction and increased vasoconstriction developed during rhabdomyolysis. .OH plays an important role in the development of these vascular responses. These findings suggest that decreased endothelium-dependent vasodilation and augmented renal sympathetic tonus contribute to the development of renal vasoconstriction during rhabdomyolysis-induced ARF.

  20. Effectiveness of Donepezil, Rivastigmine, and (±)Huperzine A in Counteracting the Acute Toxicity of Organophosphorus Nerve Agents: Comparison with Galantamine

    PubMed Central

    Aracava, Yasco; Pereira, Edna F. R.; Akkerman, Miriam; Adler, Michael

    2009-01-01

    Galantamine, a centrally acting cholinesterase (ChE) inhibitor and a nicotinic allosteric potentiating ligand used to treat Alzheimer's disease, is an effective and safe antidote against poisoning with nerve agents, including soman. Here, the effectiveness of galantamine was compared with that of the centrally active ChE inhibitors donepezil, rivastigmine, and (±)huperzine A as a pre- and/or post-treatment to counteract the acute toxicity of soman. In the first set of experiments, male prepubertal guinea pigs were treated intramuscularly with one of the test drugs and 30 min later challenged with 1.5 × LD50 soman (42 μg/kg s.c.). All animals that were pretreated with galantamine (6–8 mg/kg), 3 mg/kg donepezil, 6 mg/kg rivastigmine, or 0.3 mg/kg (±)huperzine A survived the soman challenge, provided that they were also post-treated with atropine (10 mg/kg i.m.). However, only galantamine was well tolerated. In subsequent experiments, the effectiveness of specific treatment regimens using 8 mg/kg galantamine, 3 mg/kg donepezil, 6 mg/kg rivastigmine, or 0.3 mg/kg (±)huperzine A was compared in guinea pigs challenged with soman. In the absence of atropine, only galantamine worked as an effective and safe pretreatment in animals challenged with 1.0 × LD50 soman. Galantamine was also the only drug to afford significant protection when given to guinea pigs after 1.0 × LD50 soman. Finally, all test drugs except galantamine reduced the survival of the animals when administered 1 or 3 h after the challenge with 0.6 or 0.7 × LD50 soman. Thus, galantamine emerges as a superior antidotal therapy against the toxicity of soman. PMID:19741148

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