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Spinal cord injury (SCI) leads to a loss of sensitive and motor functions. Currently, there is no therapeutic intervention offering a complete recovery. Here, we report that repetitive trans-spinal magnetic stimulation (rTSMS) can be a noninvasive SCI treatment that enhances tissue repair and functional recovery. Several techniques including immunohistochemical, behavioral, cells cultures, and proteomics have been performed. Moreover, different lesion paradigms, such as acute and chronic phase following SCI in wild-type and transgenic animals at different ages (juvenile, adult, and aged), have been used. We demonstrate that rTSMS modulates the lesion scar by decreasing fibrosis and inflammation and increases proliferation of spinal cord stem cells. Our results demonstrate also that rTSMS decreases demyelination, which contributes to axonal regrowth, neuronal survival, and locomotor recovery after SCI. This research provides evidence that rTSMS induces therapeutic effects in a preclinical rodent model and suggests possible translation to clinical application in humans. Electronic supplementary material The online version of this article (10.1007/s13311-020-00915-5) contains supplementary material, which is available to authorized users.

Sub-axial cervical spine injuries are commonly seen in patients with blunt trauma. They may be associated with spinal cord injury resulting in tetraplegia and severe permanent disability. Immobilization of the neck, maintenance of blood pressure and oxygenation, rapid clinical and radiological assessment of all injuries, and realignment of the spinal column are the key steps in the emergency management of these injuries. The role of intravenous methylprednisolone administration in acute spinal cord injuries remains controversial. The definitive management of these injuries is based upon recognition of the fracture pattern, assessment of the degree of instability, the presence or absence of neurologic deficit, and other patient related factors that may influence the outcome. Nonoperative treatment comprises of some form of external immobilization for 8 to 12 weeks, followed by imaging to assess fracture healing, and to rule out instability. The goals of surgery are realignment of the vertebral column, decompression of the neural elements and instrumented stabilization.

Objectives Pressure ulcers are frequently observed in spinal cord injury (SCI) patients. They can be life-threatening and are a major medico-economic burden. Despite their frequency, their pathophysiology and optimal management are still poorly understood. Most available data comes from non-comparative studies, especially in terms of antimicrobial use. Methods We performed a critical review of the literature and opinions of infectious disease specialists based in a French expert center for this disease. We mainly focused on antimicrobial treatments prescribed in this situation. Results These infections are usually clinically diagnosed. Microbiological samples are not the gold standard for this assessment. Furthermore, reliable microbiological identification is a major challenge but should help select antimicrobial treatment. Imaging technique could be helpful but cannot replace the physical examination. The choice of antimicrobials must consider the potential ecological collateral damages in this vulnerable population. Antimicrobial therapy should be as short as possible, adapted to the microbiological identification, and must have suitable bioavailability. Conclusion Management of infected pressure ulcers is a major concern in disabled patients already highly exposed to antimicrobial treatment and multidrug-resistant organisms colonization. Extensive data is required.

Objective:To investigate changes in body ownership and chronic neuropathic pain in patients with spinal cord injury (SCI) using multisensory own body illusions and virtual reality (VR).Methods:Twenty patients with SCI with paraplegia and 20 healthy control participants (HC) participated in 2 factorial, randomized, repeated-measures design studies. In the virtual leg illusion (VLI), we applied asynchronous or synchronous visuotactile stimulation to the participant's back (either immediately above the lesion level or at the shoulder) and to the virtual legs as seen on a VR head-mounted display. We tested the effect of the VLI on the sense of leg ownership (questionnaires) and on perceived neuropathic pain (visual analogue scale pain ratings). We compared illusory leg ownership with illusory global body ownership (induced in the full body illusion [FBI]), by applying asynchronous or synchronous visuotactile stimulation to the participant's back and the back of a virtual body as seen on a head-mounted display.Results:Our data show that patients with SCI are less sensitive to multisensory stimulations inducing illusory leg ownership (as compared to HC) and that leg ownership decreased with time since SCI. In contrast, we found no differences between groups in global body ownership as tested in the FBI. VLI and FBI were both associated with mild analgesia that was only during the VLI specific for synchronous visuotactile stimulation and the lower back position.Conclusions:The present findings show that VR exposure using multisensory stimulation differently affected leg vs body ownership, and is associated with mild analgesia with potential for SCI neurorehabilitation protocols.

International audience; OBJECTIVES: Conduct a literature review on the organization models for the chronic neuropathic pain management of spinal cord injury (SCI) patients. METHODS: Bibliographical research on Medline based on the following keywords: chronic neuropathic pain in spinal cord injury-comprehensive management-multidisciplinary approaches. RESULTS AND DISCUSSION: No data was found in the literature on this specific topic. We took the option to report the data from the French laws regarding chronic non-cancer pain management. Chronic pain in SCI patients needs a specific and rigorous approach, justifying the role of the physical medicine and rehabilitation (PM&R) physician within specialized pain management centers as a key referent physician and coordinator for this type of patient. Furthermore, SCI pain is a chronic pain and as such requires a global care management; engulfing its emotional, affective, cognitive and behavioral aspects. These particular aspects need to be evaluated within specialized centers dedicated to chronic pain that provide specific therapies such as behavioral and cognitive therapies. CONCLUSION: Specific pain management centers or hospital units remain the benchmark place for chronic pain in SCI patients. PM&R physicians play a key role in the care management of chronic SCI pain. The partnership PM&R-Pain management center aims to provide the most efficient and coordinated care for SCI patient.

International audience; OBJECTIVE: To determine whether intermittent positive-pressure breathing (IPPB) improved lung compliance, work of breathing, and respiratory function in patients with recent high spinal cord injury (SCI). DESIGN: An unblinded randomized crossover trial. SETTING: Rehabilitation hospital. PARTICIPANTS: Patients (N=14) with SCI caused by trauma within the last 6 months and located between C5 and T6. INTERVENTION: Two months of IPPB and 2 months of conventional treatment were evaluated prospectively in random order in patients with SCI. MAIN OUTCOME MEASURES: Noninvasive lung function tests and arterial blood gas measurements were obtained repeatedly in all patients. Repeated measurements of dynamic lung compliance and work of breathing as measured by computing the area enclosed between the inspiratory esophageal pressure-tidal volume curve, and the theoretical chest wall static pressure-volume curve were performed in 7 patients. RESULTS: IPPB had no long-term effects on vital capacity (52.1%+/-11.3% vs 54.5%+/-12.5%, after conventional treatment and IPPB, respectively; P=.27), lung compliance (66.4+/-48.9 mL/cmH(2)O vs 70.3+/-38.4 mL/cmH(2)O; P=.56), or other lung function tests. IPPB did not exert short-term effects on lung compliance or work of breathing. CONCLUSIONS: IPPB produced no immediate or long-term improvements in lung function or ventilatory mechanics in patients with recent SCI. (ClinicalTrials.gov identifier: NCT00476866.).

Introduction: The Restless syndrome (RLS) is a sensorimotor disorder characterized by an urgent need to move the limbs (typically the legs), associated with unpleasant feelings, painful during late afternoon or early night. Periodic leg movements (PLM) may be attached during sleep, characterized by a extension movement of the hallux, dorsiflexion of the ankle and sometimes knee flexion and hip. The pathophysiology of RLS is not fully understood.In the literature, studies have shown an increased prevalence of RLS in patients with Spinal cord Injury (SCI) or Multiple Sclerosis (MS).Objective: the diagnosis of spasticity or RLS in patients complaining of repeated nocturnal spasms initially addressed in consultation because of spasticity resisting to pharmacological treatment.Method: Prospective study, from March 2014 to June 2015, monocentric, in the MPR Service Hospital Raymond Poincaré.Inclusion criteria: age over 18 years, SCI, MS patients, with nocturnal predominance spasms. Exclusion criteria: presence of pressure sores, unable to achieve a polysomnogram. Weekday hospital patients for predominantly nocturnal spasms resistant to pharmacological treatment of spasticity orally or even to intrathecal therapy (IT) IT baclofen, associated with sleep disorders, enjoyed a polysomnography. If RLS exists, 0.18 mg of pramipexole was administered to the patient, followed by a control polysomnography.Results: 18 patients: 7 (MP), 11 (SCI) were included. All had polysomnography for a RLS. All of them had, during the medical examination, 4 main criterias of RLS & 16 of the PLM of the polysomnography record. A significant improvement was experienced on 10 patients, with a important reduction (PLM) on polysomnography control, after administration of pramipexole.Conclusion: This pilot study shows that RLS may be a differential diagnosis of spasticity. The presence of spasms with predominance nocturnal or during supine position, in patients with type of central nervous system lesions (SCI) or (MS) has to search for RLS and test the effect of dopamine agonists in case of positive diagnosis.; Introduction : Le syndrome des jambes sans repos (SJSR) est un trouble sensitivomoteur caractérisé par un besoin impérieux de bouger les membres (classiquement les jambes), associé à des sensations désagréables, parfois douloureuses en fin de journée ou début de nuit. Des mouvements périodiques des jambes (MPJ) peuvent être associés, durant le sommeil, caractérisé par un mouvement d’extension de l’hallux, flexion dorsale de la cheville et parfois une flexion du genou et de la hanche. La physiopathologie du SJSR n’est pas entièrement élucidée. Dans la littérature, des études ont mis en évidence une prévalence augmentée du SJSR chez les patients blessés médullaires (BM) ou Sclérose en Plaque (SEP).Objectif : Faire le diagnostic de spasticité ou SJSR chez des patients se plaignant de spasmes répétés à prédominance nocturne adressés initialement en consultation pour spasticité résistant au traitement pharmacologique.Méthode : Étude prospective, de mars 2014 à juin 2015, monocentrique, dans le service de MPR de l’hôpital Raymond Poincaré. Les critères d’inclusion: âge supérieur à 18 ans, blessés médullaires, SEP, ayant des spasmes à prédominance nocturne. Les critères d’exclusion : existence d’escarres, impossibilité de réalisation d’un enregistrement polysomnographique. Les patients adressés en hôpital de semaine pour des spasmes à prédominance nocturnes résistants au traitement pharmacologique per os de la spasticité, voire même à la thérapie intra‐thécale (IT) par baclofène IT, associés à des troubles du sommeil, bénéficiaient d’une polysomnographie. En cas de SJSR, 0.18 mg de pramipexol était administré au patient, suivi d’une polysomnographie de contrôle.Résultats : 18 patients : 7 (SEP), 11 (BM) furent inclus. Tous avaient à l’interrogatoire les 4 critères essentiels au diagnostic de SJSR et 16 des MPJ sur l’enregistrement polysomnographique. Une amélioration significative fût ressentie par tous les patients, avec une réduction significative des (MPJ) sur la polysomnographie de contrôle pour 11 patients, après administration du pramipexol.Conclusion : Cette étude pilote montre que le SJSR peut représenter un diagnostic différentiel de la spasticité. La présence de spasmes, nocturnes ou lors du décubitus, chez un patient atteint de lésions du système nerveux central de type (BM) ou (SEP) doit faire rechercher un SJSR puis tester l’effet d’agonistes dopaminergiques en cas de diagnostic positif.

Combination of ex vivo gene transfer and cell transplantation is now considered as a potentially useful strategy for the treatment of spinal cord injury. In a perspective of clinical application, autologous transplantation could be an option of choice. We analyzed the fate of adult rat cortical astrocytes genetically engineered with a lentiviral vector transplanted into a lesioned rat spinal cord. Cultures of adult rat cortical astrocytes were infected with an HIV-1-derived vector (TRIP-CMV-GFP) and labeled with the fluorescent dye Hoechst. Transfected and labeled astrocyte suspension was injected at T11 in rats in which spinal cord transection at T7-T8 levels had been carried out 1 week earlier. Six weeks after grafting, the animals were sacrificed and transplants were retrieved either by Hoechst fluorescence or by immunohistochemistry for detection of glial fibrillary acidic protein (GFAP) and vimentin. Grafted astrocytes expressing green fluorescent protein (GFP) were found both at the injection and transection sites. Genetically modified astrocytes thus survived, integrated, and migrated within the host parenchyma when grafted into the completely transected rat spinal cord. In addition, they retained some ability to express the GFP transgene for at least 6 weeks after transplantation. Adult astrocytes infected with lentiviral vectors can therefore be a valuable tool for the delivery of therapeutic factors into the lesioned spinal cord., Contract grant sponsor: Institut de Recherche sur la Moelle Epiniere;Contract grant sponsor: Association Francaise des Myopathies.

Despite limited regeneration capacity, partial injuries to the adult mammalian spinal cord can elicit variable degrees of functional recovery, mediated at least in part by reorganization of neuronal circuitry. Underlying mechanisms are believed to include synaptic plasticity and collateral sprouting of spared axons. Because plasticity is higher in young animals, we developed a spinal cord compression (SCC) injury model in the neonatal mouse to gain insight into the potential for reorganization during early life. The model provides a platform for high-throughput assessment of functional synaptic connectivity that is also suitable for testing the functional integration of human stem and progenitor cell-derived neurons being considered for clinical cell replacement strategies. SCC was generated at T9–T11 and functional recovery was assessed using an integrated approach including video kinematics, histology, tract tracing, electrophysiology, and high-throughput optical recording of descending inputs to identified spinal neurons. Dramatic degeneration of axons and synaptic contacts was evident within 24 hours of SCC, and loss of neurons in the injured segment was evident for at least a month thereafter. Initial hindlimb paralysis was paralleled by a loss of descending inputs to lumbar motoneurons. Within 4 days of SCC and progressively thereafter, hindlimb motility began to be restored and descending inputs reappeared, but with examples of atypical synaptic connections indicating a reorganization of circuitry. One to two weeks after SCC, hindlimb motility approached sham control levels, and weight-bearing locomotion was virtually indistinguishable in SCC and sham control mice. Genetically labeled human fetal neural progenitor cells injected into the injured spinal cord survived for at least a month, integrated into the host tissue and began to differentiate morphologically. This integrative neonatal mouse model provides opportunities to explore early adaptive plasticity mechanisms underlying functional recovery as well as the capacity for human stem cell-derived neurons to integrate functionally into spinal circuits. © 2013 Boulland et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

International audience; Repeated in vivo two-photon imaging of adult mammalian spinal cords, with subcellular resolution, would be crucial for understanding cellular mechanisms under normal and pathological conditions. Current methods are limited because they require surgery for each imaging session. Here we report a simple glass window methodology avoiding repeated surgical procedures and subsequent inflammation. We applied this strategy to follow axon integrity and the inflammatory response over months by multicolour imaging of adult transgenic mice. We found that glass windows have no significant effect on axon number or structure, cause a transient inflammatory response, and dramatically increase the throughput of in vivo spinal imaging. Moreover, we used this technique to track retraction/degeneration and regeneration of cut axons after a 'pin-prick' spinal cord injury with high temporal fidelity. We showed that regenerating axons can cross an injury site within 4 days and that their terminals undergo dramatic morphological changes for weeks after injury. Overall the technique can potentially be adapted to evaluate cellular functions and therapeutic strategies in the normal and diseased spinal cord.

National audience; Objective To evaluate the impact of age (< or ≥ 65 ans) on hospital mortality in traumatic spinal cord injury requiring intensive care. Design Retrospective, monocenter. Patients and methods A total of 131 patients greater or equal to 15 years (< 65 years, n = 109 and ≥ 65 years, n = 22) was analyzed (cervical, n = 71; thoracolumbar, n = 60), over a 10 years period (1998-2008). The hospital and long-term mortality were studied. The risks factors of death were searched by a uni- and multivariate analysis. Intensive care unit (ICU) discharge and long-term neurological recovery, and long-term functional independence measure (FIM) were assessed. Results Hospital mortality was increased in patients greater or equal to 65 years (41% vs 6%, P < 0.001) and long term mortality was not different between the two groups (31% vs 12%, P = 0.150). The risks factors of death were age (HR = 3.44; IC 95%: 1.53-7.72, P = 0.028), previous coronary disease (HR = 3.64; IC 95%: 1.25-10.65; P = 0.018) and fall injury (HR = 2.40; IC 95%: 1.15-5.00, P = 0.020). Among survivors, incompletes forms (Frankel B, C, D, E) were significantly more frequent in older patients at ICU discharge and long term follow up. At long term, FIM was similar in the two groups except a better sphincter control in patient greater or equal to 65 years. Conclusion Mortality rate of older people (≥ 65 years) were greater than those in younger people, mainly caused by an increased hospital mortality. Among survivors, the neurological recovery was better in patients' greater or equal to 65 years, and was associated with a functional status at least comparable than in the youngest patients.

French version available; International audience; PURPOSE: The perception of verticality results from the integration of vestibular, visual and somatosensory information. Spinal cord injured patients with complete paraplegia have total somatosensory deafferentation below a certain metameric segment. In our study, we were interested in the implication of somatosensory signal in the construction of verticality and in the possible effect of somatosensory loss on spatial representation. METHOD: We analysed haptic and postural aspects of perceived verticality in 14 spinal cord injured patients with complete paraplegia and in an age- and gender-matched group of 13 controls. We also conducted a structured interview on the existence of vertigo or postural instability in daily life. RESULTS: The spinal cord injured patients perceived verticality without any significant directional bias in the orientation of the vertical but with a greater uncertainty than control subjects, both in haptic and postural modalities. If paraplegic did not report vertigo, half described an altered spatial perception without vision. CONCLUSION: The present results confirm the importance of sensory input from the trunk and the lower limbs in the perception of the vertical. However, visual and vestibular information appear to compensate for somatosensory deafferentation.

International audience; Engraftment of nasal olfactory ensheathing cells (OEC) is considered as a promising therapeutic strategy for spinal cord repair and one clinical trial has already been initiated. However, while the vast majority of fundamental studies were focused on the recovery of locomotor function, the efficiency of this cellular tool for repairing respiratory motor dysfunction, which affects more than half of paraplegic/tetraplegic patients, remains unknown. Using a rat model that mimics the mechanisms encountered after a cervical contusion that induces a persistent hemi-diaphragmatic paralysis, we assessed the therapeutic efficiency of a delayed transplantation (2 weeks post-contusion) of nasal OECs within the injured spinal cord. Functional recovery was quantified with respiratory behavior tests, diaphragmatic electromyography and neuro-electrophysiological recording of the phrenic motoneurons while axogenesis was evaluated using immunohistochemistry. We show that 3 months post-transplantation, nasal OECs improve i) breathing movements, ii) activities of the ipsilateral diaphragm and corresponding phrenic nerve, and iii) axonal sprouting in the injury site. We also demonstrate that this functional partial recovery is mediated by the restoration of ipsilateral supraspinal command. Our study brings further evidence that olfactory ensheathing cells could have clinical application especially in tetraplegic patients with impaired breathing movements. This article is part of a Special Issue entitled: Understanding olfactory ensheathing glia and their prospect for nervous system repair.

International audience; The rodent respiratory system is a relevant model for study of the intrinsic post-lesion mechanisms of neuronal plasticity and resulting recovery after high cervical spinal cord injury. An unilateral cervical injury (hemisection, lateral section or contusion) interrupts unilaterally bulbospinal respiratory pathways to phrenic motor neurons innervating the diaphragm and leads to important respiratory defects on the injured side. However, the ipsilateral phrenic nerve exhibits a spontaneous and progressive recovery with post-lesion time. Shortly after a lateral injury, this partial recovery depends on the activation of contralateral pathways that cross the spinal midline caudal to the injury. Activation of these crossed phrenic pathways after the injury depends on the integrity of phrenic sensory afferents. These pathways are located principally in the lateral part of the spinal cord and involve 30% of the medullary respiratory neurons. By contrast, in chronic post-lesion conditions, the medial part of the spinal cord becomes sufficient to trigger substantial ipsilateral respiratory drive. Thus, after unilateral cervical spinal cord injury, respiratory reactivation is associated with a time-dependent anatomo-functional reorganization of the bulbospinal respiratory descending pathways, which represents an adaptative strategy for functional compensation.

International audience; OBJECTIVE: To determine whether intermittent positive-pressure breathing (IPPB) improved lung compliance, work of breathing, and respiratory function in patients with recent high spinal cord injury (SCI). DESIGN: An unblinded randomized crossover trial. SETTING: Rehabilitation hospital. PARTICIPANTS: Patients (N=14) with SCI caused by trauma within the last 6 months and located between C5 and T6. INTERVENTION: Two months of IPPB and 2 months of conventional treatment were evaluated prospectively in random order in patients with SCI. MAIN OUTCOME MEASURES: Noninvasive lung function tests and arterial blood gas measurements were obtained repeatedly in all patients. Repeated measurements of dynamic lung compliance and work of breathing as measured by computing the area enclosed between the inspiratory esophageal pressure-tidal volume curve, and the theoretical chest wall static pressure-volume curve were performed in 7 patients. RESULTS: IPPB had no long-term effects on vital capacity (52.1%+/-11.3% vs 54.5%+/-12.5%, after conventional treatment and IPPB, respectively; P=.27), lung compliance (66.4+/-48.9 mL/cmH(2)O vs 70.3+/-38.4 mL/cmH(2)O; P=.56), or other lung function tests. IPPB did not exert short-term effects on lung compliance or work of breathing. CONCLUSIONS: IPPB produced no immediate or long-term improvements in lung function or ventilatory mechanics in patients with recent SCI. (ClinicalTrials.gov identifier: NCT00476866.).

Intrathecal clonidine has been tested in spinal cord injury patients not supporting or resistant to anticholinergic drugs. Although the acute effect of clonidine on urodynamic parameters was satisfactory, cardiovascular adverse effects limited the long-term efficacy of this treatment. Intrathecal baclofen has a limited effect on overactive bladder in patients with spinal spasticity, but can modify the quality of erections and induce an incapacity to trigger ejaculation by vibratory penile stimulation.

Objective: To prospectively evaluate the effect of pump-infused intrathecal baclofen infusion (ITB) in therapeutic doses on sleep quality and on daytime and nighttime respiratory function in patients with severe spasticity. Methods: We prospectively evaluated 20 consecutive patients (mean ± SD age 45 ± 13 years). We assessed spasticity and obtained polysomnography, pulmonary function tests, and resting energy expenditure measurements 1 week before and at least 8 days after pump implantation. Patients stopped oral baclofen upon pump implantation but continued other medications unchanged. We report descriptive statistics as means ± SD. Results: Most of the patients had multiple sclerosis (n = 9) or spinal cord injury (n = 8); there was one case each of cerebral palsy, hereditary spastic paraplegia, and Friedreich ataxia. Before and after ITB initiation, mean Ashworth scores were 2.75 ± 0.85 and 1.15 ± 0.36, and mean spasm scores were 3.75 ± 0.55 and 1.00 ± 0.56. ITB improved total sleep time ( p = 0.05) and sleep efficiency ( p = 0.01) and reduced periodic leg movements ( p = 0.02). ITB did not modify sleep-related respiratory events, lung function tests, CO 2 rebreathing response, or resting energy expenditure. Conclusion: Compared with oral baclofen, intrathecal baclofen infusion did not affect respiratory function and improved sleep continuity. Intrathecal baclofen infusion in therapeutic doses may act at the spinal level rather than at the supraspinal level.

INTRODUCTION: C2 spinal cord hemisection interrupts descending bulbospinal respiratory axons coursing through the cervical spinal cord. One consequence of this type of spinal cord injury is the partial deafferentation of the ipsilateral phrenic nucleus, which renders the hemidiaphragm paralysed. The biochemical properties of the intact or denervated locomotor skeletal muscles have been studied extensively, whereas the biochemical properties of the diaphragm after a cervical spinal cord injury received relatively little attention. This seems unfortunate, given that the diaphragm is the most important mammalian respiratory muscle and is the only skeletal muscle considered essential for survival. Therefore, the purpose of this work was to analyse the bioenergetic characteristics of the diaphragm following a cervical spinal cord injury. METHODS: Segments of the crural diaphragm from rat were homogenised to determine the activities of a glycolytic enzyme, lactate dehydrogenase (LDH), and a Krebs cycle enzyme, citrate synthase (CS). RESULTS: Data show a significant decrease of the CS activity on the ipsilateral hemidiaphragm to the cervical hemisection. No change in the LDH is observed between the animal without or with a cervical spinal cord injury. CONCLUSIONS: These data suggested that the CS activity could be dependent of the nervous influx from the central respiratory rhythm generator and that LDH activity could be maintained by a peripheral respiratory activity or by the cross phrenic phenomenon activation. Biochemical data should be considered in subjects presenting respiratory deficiency induced by a cervical spinal cord injury. Furthermore, the diaphragmatic muscle metabolic activity could be used to evaluate the functional respiratory recovery observed spontaneously or experimentally after using repair strategies of the spinal cord.

International audience; Autonomic dysreflexia (AD) occurs in a majority of high paraplegic and quadriplegic patients and is particularly characterized by a paroxysmal hypertension elicited by somatic or visceral stimuli. We have previously shown that plasma adrenaline and noradrenaline levels were significantly increased during episodes of AD in the 30-day spinal cord-injured (SCI) rats, suggesting the participation of adrenal catecholamines in the cardiovascular changes associated to AD. Thus, adrenal sympathetic preganglionic neurons (SPN) could be activated by visceral afferences leading to AD. The aim of this study was then to demonstrate whether visceral stimulation that induces AD activates adrenal SPN in chronic SCI rats. To this end, a retrograde tracer, the cholera toxin B subunit (CTB), was combined with the immunocytochemical detection of Fos protein after visceral stimulation. Chronic SCI rats received a CTB injection into the adrenal gland and, 3 days later, were stimulated by repetitive distension of the colon. Results showed that this stimulation elicited typical hypertensive episodes of AD and a significant increase in the number of double-labeled neurons (CTB/Fos immunoreactive neurons) in the thoracic spinal cord below the level of injury (T4 segment) when compared to the stimulated non-SCI rats. In conclusion, visceral stimulations in the chronic SCI rats activate adrenal SPN, which could induce release of catecholamines by the adrenal medulla. The present study brings new data on the spinal mechanisms of AD cardiovascular dysfunctions.

International audience; The aim of this study was to validate an incremental field test performed by wheelchair-dependent (WD) athletes. Nine male paraplegic subjects (mean age 28.9 +/- 4.2 years) performed an incremental field test (FT) and a comparable laboratory test (LT) with their own usual wheelchairs. Both tests started with an initial speed of 4 km.hr(-1) and increased by increments of 1 km.hr(-1) every minute until volitional exhaustion. The FT was an adapted Léger and Boucher test (ALBT) and was conducted on a 400 m tartan field marked-off every 50 m with pylons. Ventilatory data were collected every 15 s using a portable telemetric system (Cosmed K2, JFB International, Italy). The LT was performed on an adapted treadmill (Sopur, Germany) and ventilatory data were collected every minute using a breath-by-breath automated system (CPX, Medical Graphics, MN, USA). The LT and the FT were not significantly different for duration (8 min 50 +/- 1 min 24 vs 9 min 55 +/- 29 s), percentage of maximal heart rate (HR, 86.2 +/- 3.9 vs 89.7 +/- 5.3%), maximal minute ventilation (VE, 101.6 +/- 28.5 vs 96.8 +/- 28.2 1.min(-1)) and peak oxygen uptake (VO2 peak, 39.7 + 7.3 vs 36.1 + 5.8 ml.kg(-1).min(-1) assessed with the CPX and the K2, respectively. We concluded that the FT proposed in the present study is a valid test for direct VO2 peak assessment in wheelchair athletes using a portable VO2 telemetric system. Nonetheless, the Léger and Mercier model equation did not accurately predict VO2 max and further investigation is needed to determine a valid VO2 max prediction equation for these subjects during the FT.