scholarly journals Long-duration perforated patch recordings from spinal interneurons of adult mice

2011 ◽  
Vol 106 (5) ◽  
pp. 2783-2789 ◽  
Author(s):  
Andreas Husch ◽  
Nathan Cramer ◽  
Ronald M. Harris-Warrick
Keyword(s):  
Spinal Cord ◽  
Drug Application ◽  
Lumbar Spinal Cord ◽  
Spinal Cord Neurons ◽  
Perforated Patch ◽  
Adult Mice ◽  
Vital Functions ◽  
Cord Injury ◽  
Lumbar Spinal

It has been very difficult to record from interneurons in acute slices of the lumbar spinal cord from mice >3 wk of age. The low success rate and short recording times limit in vitro experimentation on mouse spinal networks to neonatal and early postnatal periods when locomotor networks are still developmentally immature. To overcome this limitation and enable investigation of mature locomotor network neurons, we have established a reliable procedure to record from spinal cord neurons in slices from adult, behaviorally mature mice of any age. Two key changes to the established neonate procedure were implemented. First, we remove the cord by a dorsal laminectomy from a deeply anesthetized animal. This enables respiration and other vital functions to continue up to the moment the maximally oxygenated lumbar spinal cord is removed, improving the health of the slices. Second, since adult spinal cord interneurons appear more sensitive to the intracellular dialysis that occurs during whole cell recordings, we introduced perforated patch recordings to the procedure. Stable recordings up to 12 h in duration were obtained with our new method. This will allow investigation of changes in mature neuronal properties in disease states or after spinal cord injury and allow prolonged recordings of responses to drug application that were previously impossible.

scholarly journals Multi-pronged neuromodulation intervention engages the residual motor circuitry to facilitate walking in a rat model of spinal cord injury

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Marco Bonizzato ◽  
Nicholas D. James ◽  
Galyna Pidpruzhnykova ◽  
Natalia Pavlova ◽  
Polina Shkorbatova ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Rat Model ◽  
Stress Responses ◽  
Learning Algorithm ◽  
Lumbar Spinal Cord ◽  
Cord Injury ◽  
Potential Synergy ◽  
Lumbar Spinal ◽  
Deep Brain

AbstractA spinal cord injury usually spares some components of the locomotor circuitry. Deep brain stimulation (DBS) of the midbrain locomotor region and epidural electrical stimulation of the lumbar spinal cord (EES) are being used to tap into this spared circuitry to enable locomotion in humans with spinal cord injury. While appealing, the potential synergy between DBS and EES remains unknown. Here, we report the synergistic facilitation of locomotion when DBS is combined with EES in a rat model of severe contusion spinal cord injury leading to leg paralysis. However, this synergy requires high amplitudes of DBS, which triggers forced locomotion associated with stress responses. To suppress these undesired responses, we link DBS to the intention to walk, decoded from cortical activity using a robust, rapidly calibrated unsupervised learning algorithm. This contingency amplifies the supraspinal descending command while empowering the rats into volitional walking. However, the resulting improvements may not outweigh the complex technological framework necessary to establish viable therapeutic conditions.

Features of laminar and somatotopic organization of lumbar spinal cord units receiving cutaneous inputs from hindlimb receptive fields

1984 ◽  
Vol 52 (3) ◽  
pp. 449-458 ◽  
Author(s):  
A. R. Light ◽  
R. G. Durkovic
Keyword(s):  
Spinal Cord ◽  
Receptive Field ◽  
Receptive Fields ◽  
Lumbar Spinal Cord ◽  
Spinal Neurons ◽  
Spinal Cord Neurons ◽  
Somatotopic Organization ◽  
Single Unit Recordings ◽  
Lumbar Spinal ◽  
Rectangular Columns

Single-unit recordings from 312 units of lamina I-VII of the lumbar spinal cord of unanesthetized, decerebrate, T8 spinal cats were used to determine the somatotopic and laminar organization of spinal neurons responding to cutaneous stimulation of the hindlimb. Properties of cells confined to different Rexed laminae (I-VII) were shown to differ in several respects, including responses to variations in stimulus intensity, receptive-field areas, spontaneous frequencies, and central delays. Spinal cord neurons with similarly localized cutaneous receptive fields were found to be organized in sagittally oriented rectangular columns. These columns were 7 to at least 20 mm long (rostral-caudal axis), 0.5-1.0 mm wide, and could encompass laminae I-VII in depth. Touch, pressure, and pinch were effective excitatory inputs into each column subserving a given receptive-field location. A map of the somatotopic organization of units in the horizontal plane is presented, which in general confirms previous reports and in particular deals with the organization of units with receptive fields on the plantar cushion and individual toes.

Development of Polymeric Nerve Guidance Conduits That Contain Anisotropic Cues Including Aligned Microfibers and Gradients of Adsorbed Laminin-1

2008 ◽  
Vol 2 (2) ◽  
Author(s):  
Jared M. Cregg ◽  
Han Bing Wang ◽  
Michael E. Mullins ◽  
Ryan J. Gilbert
Keyword(s):  
Spinal Cord ◽  
Electrospun Fiber ◽  
Axonal Growth ◽  
Contact Guidance ◽  
Directional Growth ◽  
Spinal Cord Neurons ◽  
Neurite Extension ◽  
Cord Injury ◽  
Laminin 1

Structures that direct neurite extension are important for regeneration following spinal cord injury and peripheral nerve injury. Within the spinal cord, neurons encounter a glial scar environment that impedes regeneration. In the peripheral nervous system, endogenous regeneration cannot occur across nerve gaps greater than 2mm. Current repair strategies use guidance conduits to channel axonal growth towards distal targets. While showing promise, conduit walls do not provide a suitable environment for neuronal attachment or extension, and axonal growth within conduits remains tortuous. Hence, there is a need for development of three-dimensional (3D) structures that use contact guidance—rather than confinement—as a means of guided regeneration. Our laboratory has developed aligned, electrospun fiber matrices that have been shown to direct neurite extension in vitro. In addition, a gradient of the glycoprotein laminin-1 has been adsorbed onto aligned microfiber matrices to stimulate directional growth. These matrices were then manipulated into 3D conduit structures. Novel polymeric conduits that utilize contact guidance and contain gradients of molecules that stimulate directional growth have the potential to foster fast, directed regeneration into and through conduit structures.

scholarly journals Locomotor Training Increases Synaptic Structure With High NGL-2 Expression After Spinal Cord Hemisection

2019 ◽  
Vol 33 (3) ◽  
pp. 225-231 ◽  
Author(s):  
Kazu Kobayakawa ◽  
Kyleigh Alexis DePetro ◽  
Hui Zhong ◽  
Bau Pham ◽  
Masamitsu Hara ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Motor Neurons ◽  
Ventral Horn ◽  
Lumbar Spinal Cord ◽  
Locomotor Training ◽  
Synaptic Structure ◽  
Cord Injury ◽  
Lumbar Spinal ◽  
Spinal Cord Hemisection ◽  
Activity Dependent

Background. We previously demonstrated that step training leads to reorganization of neuronal networks in the lumbar spinal cord of rodents after a hemisection (HX) injury and step training, including increases excitability of spinally evoked potentials in hindlimb motor neurons. Methods. In this study, we investigated changes in RNA expression and synapse number using RNA-Seq and immunohistochemistry of the lumbar spinal cord 23 days after a mid-thoracic HX in rats with and without post-HX step training. Results. Gene Ontology (GO) term clustering demonstrated that expression levels of 36 synapse-related genes were increased in trained compared with nontrained rats. Many synaptic genes were upregulated in trained rats, but Lrrc4 (coding NGL-2) was the most highly expressed in the lumbar spinal cord caudal to the HX lesion. Trained rats also had a higher number of NGL-2/synaptophysin synaptic puncta in the lumbar ventral horn. Conclusions. Our findings demonstrate clear activity-dependent regulation of synapse-related gene expression post-HX. This effect is consistent with the concept that activity-dependent phenomena can provide a mechanistic drive for epigenetic neuronal group selection in the shaping of the reorganization of synaptic networks to learn the locomotion task being trained after spinal cord injury.

scholarly journals 1H-MRS in spinal cord injury: acute and chronic metabolite alterations in rat brain and lumbar spinal cord

2011 ◽  
Vol 33 (4) ◽  
pp. 678-688 ◽  
Author(s):  
Matthias Erschbamer ◽  
Johanna Öberg ◽  
Eric Westman ◽  
Rouslan Sitnikov ◽  
Lars Olson ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Rat Brain ◽  
Lumbar Spinal Cord ◽  
1H Mrs ◽  
Cord Injury ◽  
Lumbar Spinal

The Effect Of Treadmill Training On Igf-1 Levels In Rat Skeletal Muscle And Lumbar Spinal Cord Following Spinal Cord Injury

2007 ◽  
Vol 39 (Supplement) ◽  
pp. S313
Author(s):  
Min Liu ◽  
Jennifer E. Stevens ◽  
Glenn A. Walter ◽  
Prodip Bose ◽  
Floyd J. Thompson ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Treadmill Training ◽  
Lumbar Spinal Cord ◽  
Rat Skeletal Muscle ◽  
Cord Injury ◽  
Lumbar Spinal

scholarly journals Tail Nerve Electrical Stimulation and Electro-Acupuncture Can Protect Spinal Motor Neurons and Alleviate Muscle Atrophy after Spinal Cord Transection in Rats

2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Yu-Ting Zhang ◽  
Hui Jin ◽  
Jun-Hua Wang ◽  
Lan-Yu Wen ◽  
Yang Yang ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Electrical Stimulation ◽  
Muscle Atrophy ◽  
Motor Neurons ◽  
Lumbar Spinal Cord ◽  
Hindlimb Muscle ◽  
Neurotrophin 3 ◽  
Spinal Cord Segment ◽  
Cord Injury ◽  
Lumbar Spinal

Spinal cord injury (SCI) often results in death of spinal neurons and atrophy of muscles which they govern. Thus, following SCI, reorganizing the lumbar spinal sensorimotor pathways is crucial to alleviate muscle atrophy. Tail nerve electrical stimulation (TANES) has been shown to activate the central pattern generator (CPG) and improve the locomotion recovery of spinal contused rats. Electroacupuncture (EA) is a traditional Chinese medical practice which has been proven to have a neural protective effect. Here, we examined the effects of TANES and EA on lumbar motor neurons and hindlimb muscle in spinal transected rats, respectively. From the third day postsurgery, rats in the TANES group were treated 5 times a week and those in the EA group were treated once every other day. Four weeks later, both TANES and EA showed a significant impact in promoting survival of lumbar motor neurons and expression of choline acetyltransferase (ChAT) and ameliorating atrophy of hindlimb muscle after SCI. Meanwhile, the expression of neurotrophin-3 (NT-3) in the same spinal cord segment was significantly increased. These findings suggest that TANES and EA can augment the expression of NT-3 in the lumbar spinal cord that appears to protect the motor neurons as well as alleviate muscle atrophy.

scholarly journals Nimodipine Promotes Functional Recovery After Spinal Cord Injury in Rats

2021 ◽  
Vol 12 ◽  
Author(s):  
Fangliang Guo ◽  
Xiaolong Zheng ◽  
Ziyu He ◽  
Ruoying Zhang ◽  
Song Zhang ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Motor Neurons ◽  
Hind Limb ◽  
Term Treatment ◽  
Bladder Function ◽  
Lumbar Spinal Cord ◽  
Long Term Treatment ◽  
Cord Injury ◽  
Lumbar Spinal

Spinal cord injury (SCI) is a devastating condition that results in severe motor, sensory, and autonomic dysfunction. The L-/T-type calcium channel blocker nimodipine (NMD) exerts a protective effect on neuronal injury; however, the protective effects of long-term administration of NMD in subjects with SCI remain unknown. Thus, the aim of this study was to evaluate the role of long-term treatment with NMD on a clinically relevant SCI model. Female rats with SCI induced by 25 mm contusion were subcutaneously injected with vehicle or 10 mg/kg NMD daily for six consecutive weeks. We monitored the motor score, hind limb grip strength, pain-related behaviors, and bladder function in this study to assess the efficacy of NMD in rats with SCI. Rats treated with NMD showed improvements in locomotion, pain-related behaviors, and spasticity-like symptoms, but not in open-field spontaneous activity, hind limb grip strength or bladder function. SCI lesion areas and perilesional neuronal numbers, gliosis and calcitonin gene-related peptide (CGRP+) fiber sprouting in the lumbar spinal cord and the expression of K+–Cl− cotransporter 2 (KCC2) on lumbar motor neurons were also observed to further explore the possible protective mechanisms of NMD. NMD-treated rats showed greater tissue preservation with reduced lesion areas and increased perilesional neuronal sparing. NMD-treated rats also showed improvements in gliosis, CGRP+ fiber sprouting in the lumbar spinal cord, and KCC2 expression in lumbar motor neurons. Together, these results indicate that long-term treatment with NMD improves functional recovery after SCI, which may provide a potential therapeutic strategy for the treatment of SCI.

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