Comparison of effect of crush or transection peripheral nerve lesion on lumbar spinal cord synaptic plasticity and microglial dynamics

Epidural electrical stimulation (ES) of the lumbar spinal cord combined with daily locomotor training has been demonstrated to enhance stepping ability after complete spinal transection in rodents and clinically complete spinal injuries in humans. Although functional gain is observed, plasticity mechanisms associated with such recovery remain mostly unclear. Here, we investigated how ES and locomotor training affected expression of chondroitin sulfate proteoglycans (CSPG), perineuronal nets (PNN), and synaptic plasticity on spinal motoneurons. To test this, adult rats received a complete spinal transection (T9–T10) followed by daily locomotor training performed under ES with administration of quipazine (a serotonin (5-HT) agonist) starting 7 days post-injury (dpi). Excitatory and inhibitory synaptic changes were examined at 7, 21, and 67 dpi in addition to PNN and CSPG expression. The total amount of CSPG expression significantly increased with time after injury, with no effect of training. An interesting finding was that γ-motoneurons did not express PNNs, whereas α-motoneurons demonstrated well-defined PNNs. This remarkable difference is reflected in the greater extent of synaptic changes observed in γ-motoneurons compared to α-motoneurons. A medium negative correlation between CSPG expression and changes in putative synapses around α-motoneurons was found, but no correlation was identified for γ-motoneurons. These results suggest that modulation of γ-motoneuron activity is an important mechanism associated with functional recovery induced by locomotor training under ES after a complete spinal transection.

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Changes in the somatotopic organization of the cat lumbar spinal cord following peripheral nerve transection and regeneration

Brain Research ◽

10.1016/0006-8993(83)91064-8 ◽

1983 ◽

Vol 259 (1) ◽

pp. 31-39 ◽

Cited By ~ 71

Author(s):

S.J.W. Lisney

Keyword(s):

Spinal Cord ◽

Peripheral Nerve ◽

Lumbar Spinal Cord ◽

Nerve Transection ◽

Somatotopic Organization ◽

Lumbar Spinal

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Substance P immunoreactivity in the lumbar spinal cord of the turtle Trachemys dorbigni following peripheral nerve injury

Brazilian Journal of Medical and Biological Research ◽

10.1590/s0100-879x2003000400015 ◽

2003 ◽

Vol 36 (4) ◽

pp. 515-520 ◽

Cited By ~ 6

Author(s):

W.A. Partata ◽

A.M.R. Krepsky ◽

L.L. Xavier ◽

M. Marques ◽

M. Achaval

Keyword(s):

Spinal Cord ◽

Substance P ◽

Peripheral Nerve ◽

Nerve Injury ◽

Peripheral Nerve Injury ◽

Lumbar Spinal Cord ◽

Lumbar Spinal

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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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