Functional involvement of the lumbar spinal cord after contusion to T8 spinal segment of the rat

Several experiments have demonstrated that rostral segments of the vertebrate lumbar spinal cord produce a rhythmic motor output more readily and of better quality than caudal segments. Here we examine how this rostrocaudal gradient of rhythmogenic capability is reflected in the spike activity of neurons in the rostral (L2) and caudal (L5) lumbar spinal cord of the neonatal rat. The spike activity of interneurons in the ventromedial cord, a region necessary for the production of locomotion, was recorded intracellularly with patch electrodes and extracellularly with tetrodes during pharmacologically induced locomotion. Both L2 and L5 neurons tended to be active in phase with their homologous ventral root. L5 neurons, however, had a wider distribution of their preferred phases of activity throughout the locomotor cycle than L2 neurons. The strength of modulation of the activity of individual L2 neurons was also larger than that of L5 neurons. These differences resulted in a stronger rhythmic signal from the L2 neuronal population than from the L5 population. These results demonstrate that the rhythmogenic capability of each spinal segment was reflected in the activity of interneurons located in the same segment. In addition to paralleling the rostrocaudal gradient of rhythmogenic capability, these results further suggest a colocalization of motoneurons and their associated interneurons involved in the production of locomotion.

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Lipomeningocele associated with diplomyelia in a dog

Tierärztliche Praxis Ausgabe K Kleintiere / Heimtiere ◽

10.15654/tpk-170751 ◽

2018 ◽

Vol 46 (05) ◽

pp. 323-329 ◽

Cited By ~ 2

Author(s):

Nele Ondreka ◽

Sara Malberg ◽

Emma Laws ◽

Martin Schmidt ◽

Sabine Schulze

Keyword(s):

Spinal Cord ◽

Neurological Status ◽

Split Cord Malformation ◽

Lumbar Spinal Cord ◽

Histopathological Diagnosis ◽

Type I ◽

Thoracic Spinal Cord ◽

Thoracic Spinal ◽

Subcutaneous Mass ◽

Lumbar Spinal

SummaryA 2-year-old male neutered mixed breed dog with a body weight of 30 kg was presented for evaluation of a soft subcutaneous mass on the dorsal midline at the level of the caudal thoracic spine. A further clinical sign was intermittent pain on palpation of the area of the subcutaneous mass. The owner also described a prolonged phase of urination with repeated interruption and re-initiation of voiding. The findings of the neurological examination were consistent with a lesion localization between the 3rd thoracic and 3rd lumbar spinal cord segments. Magnetic resonance imaging revealed a spina bifida with a lipomeningocele and diplomyelia (split cord malformation type I) at the level of thoracic vertebra 11 and 12 and secondary syringomyelia above the aforementioned defects in the caudal thoracic spinal cord. Surgical resection of the lipomeningocele via a hemilaminectomy was performed. After initial deterioration of the neurological status postsurgery with paraplegia and absent deep pain sensation the dog improved within 2 weeks to non-ambulatory paraparesis with voluntary urination. Six weeks postoperatively the dog was ambulatory, according to the owner. Two years after surgery the owner recorded that the dog showed a normal gait, a normal urination and no pain. Histopathological diagnosis of the biopsied material revealed a lipomeningocele which confirmed the radiological diagnosis.

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Faculty Opinions recommendation of Functional organization of locomotor interneurons in the ventral lumbar spinal cord of the newborn rat.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.13601956.14995056 ◽

2012 ◽

Author(s):

Serge Rossignol

Keyword(s):

Spinal Cord ◽

Functional Organization ◽

Lumbar Spinal Cord ◽

Newborn Rat ◽

Lumbar Spinal

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Faculty Opinions recommendation of Neurologic improvement after thoracic, thoracolumbar, and lumbar spinal cord (conus medullaris) injuries.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.8263956.8692054 ◽

2011 ◽

Author(s):

Carlos Bagley

Keyword(s):

Spinal Cord ◽

Conus Medullaris ◽

Lumbar Spinal Cord ◽

Lumbar Spinal

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Aging process of the human lumbar spinal cord: A morphometric analysis

Neuropathology ◽

10.1111/j.1440-1789.1996.tb00164.x ◽

1996 ◽

Vol 16 (2) ◽

pp. 106-111 ◽

Cited By ~ 5

Author(s):

Ming Zhou ◽

Noboru Goto ◽

Chen Zhang ◽

Wei Tang

Keyword(s):

Spinal Cord ◽

Morphometric Analysis ◽

Aging Process ◽

Lumbar Spinal Cord ◽

Lumbar Spinal

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

Nature Communications ◽

10.1038/s41467-021-22137-9 ◽

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.

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