Analysis of the effects of 4-amino pyridine on the lumbar spinal cord of the cat. II—modifications of certain spinal inhibitory phenomena, post-tetanic potentiation and dorsal root potentials

1973 ◽  
Vol 12 (7) ◽  
pp. 641-651 ◽  
Author(s):  
M. Lemeignan
Keyword(s):  
Spinal Cord ◽  
Dorsal Root ◽  
Lumbar Spinal Cord ◽  
Post Tetanic Potentiation ◽  
Lumbar Spinal ◽  
Dorsal Root Potentials

Concussive head injury producing suppression of sensory transmission within the lumbar spinal cord in cats

1985 ◽  
Vol 63 (1) ◽  
pp. 97-105 ◽  
Author(s):  
Yoichi Katayama ◽  
James D. Glisson ◽  
Donald P. Becker ◽  
Ronald L. Hayes
Keyword(s):  
Spinal Cord ◽  
Head Injury ◽  
Dorsal Root ◽  
Lumbar Spinal Cord ◽  
Primary Afferent ◽  
Sensory Transmission ◽  
General Response ◽  
Lumbar Spinal ◽  
Dorsal Root Potentials ◽  
Root Stimulation

✓ This study examines the effects of concussive levels of a fluid-percussion head injury on sensory transmission within the lumbar spinal cord of the cat. Primary afferent depolarization (PAD) was suppressed for 2 to 5 minutes following injury, as assessed by dorsal root potentials and augmentation of antidromic dorsal root potentials, both evoked by stimulation of adjacent dorsal roots. Polysynaptic reflex discharges in ventral root potentials evoked by dorsal root stimulation were also profoundly suppressed during this same period, even when spontaneous and monosynaptic reflex discharges were facilitated. Changes in PAD produced by injury were abolished by spinal cord transection, but were not affected by midpontine transection. These findings suggest that concussive head injury can produce suppression of segmental sensory transmission by neurally mediated processes involving the bulbar brain stem. Recordings of dorsal root resting potentials, antidromic dorsal root potentials, and reductions of antidromic dorsal root potentials induced by tetanic root stimulation indicated that depressed segmental sensory function produced by injury was due to suppression of postsynaptic interneuronal transmission rather than to excitability changes in primary afferent fibers. Somatosensory cortical potentials evoked by dorsal root stimulation were profoundly depressed at the same time as segmental sensory transmission was suppressed, suggesting that suppressed segmental sensory transmission may also contribute to suppression of ascending sensory transmission. It is hypothesized that transmission failure of interneuronal systems in the initial period following insult may be a general response occurring in wide areas of the central nervous system, and not restricted to areas to which mechanical stress is directly applied. This response pattern may result from indiscriminate activation of interconnected excitatory and inhibitory elements of interneuronal systems.

Expression of vesicular glutamate transporters in rat lumbar spinal cord, with a note on dorsal root ganglia

2003 ◽  
Vol 468 (3) ◽  
pp. 380-394 ◽  
Author(s):  
Marc Landry ◽  
Rabia Bouali-Benazzouz ◽  
Salah El Mestikawy ◽  
Philippe Ravassard ◽  
Fr�d�ric Nagy
Keyword(s):  
Spinal Cord ◽  
Dorsal Root Ganglia ◽  
Dorsal Root ◽  
Glutamate Transporters ◽  
Lumbar Spinal Cord ◽  
Vesicular Glutamate Transporters ◽  
Lumbar Spinal

scholarly journals Cancer pain and neuropathic pain are associated with Aβ sensory neuronal plasticity in dorsal root ganglia and abnormal sprouting in lumbar spinal cord

2018 ◽  
Vol 14 ◽  
pp. 174480691881009 ◽  
Author(s):  
Yong Fang Zhu ◽  
Jacek M Kwiecien ◽  
Wojciech Dabrowski ◽  
Robert Ungard ◽  
Kan Lun Zhu ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Neuropathic Pain ◽  
Cancer Pain ◽  
Dorsal Root Ganglia ◽  
Neuronal Plasticity ◽  
Dorsal Root ◽  
Lumbar Spinal Cord ◽  
Lumbar Spinal

Viral Delivery of NR2D Subunits Reduces Mg2+ Block of NMDA Receptor and Restores NT-3-Induced Potentiation of AMPA-Kainate Responses in Maturing Rat Motoneurons

2004 ◽  
Vol 92 (4) ◽  
pp. 2394-2404 ◽  
Author(s):  
Victor L. Arvanian ◽  
William J. Bowers ◽  
Jeffrey C. Petruska ◽  
Vladimir Motin ◽  
Honeyleen Manuzon ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Nmda Receptor ◽  
Nmda Receptors ◽  
Dorsal Root ◽  
Lumbar Spinal Cord ◽  
Rt Pcr ◽  
Synaptic Inputs ◽  
Neurotrophin 3 ◽  
Lumbar Spinal ◽  
Ventrolateral Funiculus

N-methyl-d-aspartate (NMDA) responsiveness of motoneurons declines during the initial 2 postnatal weeks due to increasing Mg2+ block of NMDA receptors. Using gene chip analyses, RT-PCR, and immunochemistry, we have shown that the NR2D subunit of the NMDA receptor (NMDAR), known to confer resistance to Mg2+ block, also declines in motoneurons during this period. We injected a viral construct (HSVnr2d) into the lumbar spinal cord on postnatal day 2 in an attempt to restore NMDAR function in motoneurons during the second postnatal week. Following HSVnr2d injection, we detected elevated levels of NR2D mRNA in spinal cord samples and NR2D protein specifically in motoneurons. These molecular changes were associated with marked functional alterations whereby NMDAR-mediated responses in motoneurons associated with both dorsal root (DR) and ventrolateral funiculus (VLF) inputs returned to values observed at E18 due to decreased Mg2+ blockade. Viruses carrying the β-galactosidase gene did not induce these effects. NT-3 is known to potentiate AMPA-kainate responses in motoneurons if the response has an NMDAR-mediated component and thus is normally ineffective during the second postnatal week. Restoration of NMDAR-mediated responsiveness in the second postnatal week was accompanied by a return of the ability of neurotrophin-3 (NT-3) to potentiate the AMPA-kainate responses produced by both DR and VLF synaptic inputs. We conclude that delivery of the gene for a specific NMDA subunit can restore properties characteristic of younger animals to spinal cord motoneurons. This approach might be useful for enhancing the function of fibers surviving in the damaged spinal cord.

Lipomeningocele associated with diplomyelia in a dog

2018 ◽  
Vol 46 (05) ◽  
pp. 323-329 ◽  
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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