scholarly journals Axonal projections of Renshaw cells in the thoracic spinal cord

2013 ◽  
Vol 1 (6) ◽  
pp. e00161 ◽  
Author(s):  
Shane A. Saywell ◽  
Timothy W. Ford ◽  
Peter A. Kirkwood
Keyword(s):  
Spinal Cord ◽  
Renshaw Cells ◽  
Thoracic Spinal Cord ◽  
Axonal Projections ◽  
Thoracic Spinal

Subgroups of Rostral Ventrolateral Medullary and Caudal Medullary Raphe Neurons Based on Patterns of Relationship to Sympathetic Nerve Discharge and Axonal Projections

1997 ◽  
Vol 77 (1) ◽  
pp. 65-75 ◽  
Author(s):  
Susan M. Barman ◽  
Gerard L. Gebber
Keyword(s):  
Spinal Cord ◽  
Sympathetic Nerve ◽  
Cell Types ◽  
Vagus Nerves ◽  
Thoracic Spinal Cord ◽  
Axonal Projections ◽  
Thoracic Spinal ◽  
Medullary Raphe ◽  
Raphe Neurons ◽  
Nerve Discharge

Barman, Susan M. and Gerard L. Gebber. Subgroups of rostral ventrolateral medullary and caudal medullary raphe neurons based on patterns of relationship to sympathetic nerve discharge and axonal projections. J. Neurophysiol. 77: 65–75, 1997. This study was designed to answer three questions concerning rostral ventrolateral medullary (RVLM) and caudal medullary raphe (CMR) neurons with activity correlated to sympathetic nerve discharge (SND). 1) What are the proportions of RVLM and CMR neurons that have activity correlated to both the cardiac-related and 10-Hz rhythms in SND, to only the 10-Hz rhythm, and to only the cardiac-related rhythm? 2) Which of these cell types project to the spinal cord? 3) Do the outputs of the cardiac-related and 10-Hz rhythm generators converge at the level of bulbospinal neurons or their antecedent interneurons? To address these issues we recorded from 44 RVLM and 48 CMR neurons with sympathetic nerve–related activity in urethan-anesthetized cats with intact carotid sinus nerves, but sectioned aortic depressor and vagus nerves. Spike-triggered averaging, arterial pulse-triggered analysis, and coherence analysis revealed that the naturally occurring discharges of 24 of these RVLM neurons and 41 of these CMR neurons were correlated to both the 10-Hz and cardiac-related rhythms in inferior cardiac postganglionic SND. The discharges of the other neurons were correlated to only the 10-Hz rhythm (15 RVLM and 6 CMR neurons) or to only the cardiac-related rhythm (5 RVLM neurons and 1 CMR neuron) in SND. The time-controlled collision test verified that 16 of 18 RVLM and 31 of 34 CMR neurons with activity correlated to both rhythms were antidromically activated by stimulation of the white matter of the first thoracic (T1) segment of the spinal cord. In contrast, only 1 of 10 RVLM neurons and 0 of 4 CMR neurons with activity correlated to only the 10-Hz rhythm could be antidromically activated by stimulation at T1. Also 0 of 3 RVLM neurons with activity correlated to only the cardiac-related rhythm in SND were antidromically activated by spinal stimulation. These data show for the first time that bulbospinal sympathetic pathways emanating from the RVLM and CMR are comprised almost exclusively of neurons whose discharges are correlated to both the cardiac-related and 10-Hz rhythms in SND. Moreover, the data support the hypothesis that the outputs of the cardiac-related and 10-Hz rhythm generators converge on RVLM and CMR bulbospinal neurons rather than on their antecedent interneurons. Finally, the data demonstrate that a substantial proportion of RVLM neurons and a small group of CMR neurons with activity correlated to SND do not project to the thoracic spinal cord. Their discharges were correlated to only one of the rhythms in SND. Their axonal trajectories and functions are unknown.

Cardiovascular neurons of brain stem with projections to spinal cord

1984 ◽  
Vol 247 (6) ◽  
pp. R1009-R1016 ◽  
Author(s):  
D. L. Brown ◽  
P. G. Guyenet
Keyword(s):  
Spinal Cord ◽  
Arterial Pressure ◽  
Ventrolateral Medulla ◽  
Cervical Cord ◽  
Thoracic Spinal Cord ◽  
Antidromic Activation ◽  
Axonal Projections ◽  
Thoracic Spinal ◽  
Cardiovascular Neurons ◽  
Pressure Changes

In urethan-anesthetized rats a portion of the rostral ventrolateral medulla, the intermediate portion of the nucleus paragigantocellularis lateralis, was explored electrophysiologically for spinally projecting cardiovascular neurons. Spinal projections were demonstrated for 48 of 300 units tested for antidromic activation following spinal cord stimulation. The cardiovascular nature of units was tested by monitoring unit activity during transient changes in arterial pressure. A total of 47 cardiovascular neurons were identified; of these, 43 showed activities inversely correlated with arterial pressure and changes in activity closely coupled in time to arterial pressure changes. At high arterial pressures these neurons also displayed activities phasically linked to the cardiac cycle. Of these 43 neurons, 13 projected to or through the thoracic cord and 5 to or through the cervical cord. Axonal conduction velocities averaged 4.7 m/s. A second type of cardiovascular neuron (4 units of 47) was found that increased activity as arterial pressure increased. Three of these neurons projected to the cord. These results provide evidence for tonically active, baroreceptor-inhibited neurons with axonal projections to the thoracic spinal cord.

Spontaneous Herniation of the Thoracic Spinal Cord: A Case Report

2001 ◽  
Vol 45 (4) ◽  
pp. 353 ◽  
Author(s):  
Sung Chan Jin ◽  
Seoung Ro Lee ◽  
Dong Woo Park ◽  
Kyung Bin Joo
Keyword(s):  
Spinal Cord ◽  
Case Report ◽  
Thoracic Spinal Cord ◽  
Thoracic Spinal ◽  
Spontaneous Herniation

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.

scholarly journals The Histopathology of Severe Graded Compression in Lower Thoracic Spinal Cord Segment of Rat, Evaluated at Late Post-injury Phase

2021 ◽  
Author(s):  
Fedorova Jana ◽  
Kellerova Erika ◽  
Bimbova Katarina ◽  
Pavel Jaroslav
Keyword(s):  
Spinal Cord ◽  
Spontaneous Recovery ◽  
Traumatic Injury ◽  
Blue Dye ◽  
Post Injury ◽  
Thoracic Spinal Cord ◽  
Thoracic Spinal ◽  
Severe Traumatic Injury ◽  
Spinal Cord Segment ◽  
Cord Injury

AbstractSpontaneous recovery of lost motor functions is relative fast in rodent models after inducing a very mild/moderate spinal cord injury (SCI), and this may complicate a reliable evaluation of the effectiveness of potential therapy. Therefore, a severe graded (30 g, 40 g and 50 g) weight-compression SCI at the Th9 spinal segment, involving an acute mechanical impact followed by 15 min of persistent compression, was studied in adult female Wistar rats. Functional parameters, such as spontaneous recovery of motor hind limb and bladder emptying function, and the presence of hematuria were evaluated within 28 days of the post-traumatic period. The disruption of the blood-spinal cord barrier, measured by extravasated Evans Blue dye, was examined 24 h after the SCI, when maximum permeability occurs. At the end of the survival period, the degradation of gray and white matter associated with the formation of cystic cavities, and quantitative changes of glial structural proteins, such as GFAP, and integral components of axonal architecture, such as neurofilaments and myelin basic protein, were evaluated in the lesioned area of the spinal cord. Based on these functional and histological parameters, and taking the animal’s welfare into account, the 40 g weight can be considered as an upper limit for severe traumatic injury in this compression model.

Superficial siderosis due to dural defect with thoracic spinal cord herniation

2012 ◽  
Vol 312 (1-2) ◽  
pp. 170-172 ◽  
Author(s):  
Giorgio B. Boncoraglio ◽  
Elena Ballabio ◽  
Alessandra Erbetta ◽  
Francesco Prada ◽  
Mario Savoiardo ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Superficial Siderosis ◽  
Dural Defect ◽  
Thoracic Spinal Cord ◽  
Thoracic Spinal ◽  
Spinal Cord Herniation

scholarly journals Sonic Hedgehog modulates the inflammatory response and improves functional recovery after spinal cord injury in a thoracic contusion–compression model

2021 ◽  
Author(s):  
Hao Zhang ◽  
Alexander Younsi ◽  
Guoli Zheng ◽  
Mohamed Tail ◽  
Anna-Kathrin Harms ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Sonic Hedgehog ◽  
Functional Recovery ◽  
Intrathecal Administration ◽  
Neuroprotective Effects ◽  
Thoracic Spinal Cord ◽  
Shh Pathway ◽  
Thoracic Spinal ◽  
Cord Injury

Abstract Purpose The Sonic Hedgehog (Shh) pathway has been associated with a protective role after injury to the central nervous system (CNS). We, therefore, investigated the effects of intrathecal Shh-administration in the subacute phase after thoracic spinal cord injury (SCI) on secondary injury processes in rats. Methods Twenty-one Wistar rats were subjected to thoracic clip-contusion/compression SCI at T9. Animals were randomized into three treatment groups (Shh, Vehicle, Sham). Seven days after SCI, osmotic pumps were implanted for seven-day continuous intrathecal administration of Shh. Basso, Beattie and Bresnahan (BBB) score, Gridwalk test and bodyweight were weekly assessed. Animals were sacrificed six weeks after SCI and immunohistological analyses were conducted. The results were compared between groups and statistical analysis was performed (p < 0.05 was considered significant). Results The intrathecal administration of Shh led to significantly increased polarization of macrophages toward the anti-inflammatory M2-phenotype, significantly decreased T-lymphocytic invasion and significantly reduced resident microglia six weeks after the injury. Reactive astrogliosis was also significantly reduced while changes in size of the posttraumatic cyst as well as the overall macrophagic infiltration, although reduced, remained insignificant. Finally, with the administration of Shh, gain of bodyweight (216.6 ± 3.65 g vs. 230.4 ± 5.477 g; p = 0.0111) and BBB score (8.2 ± 0.2 vs. 5.9 ± 0.7 points; p = 0.0365) were significantly improved compared to untreated animals six weeks after SCI as well. Conclusion Intrathecal Shh-administration showed neuroprotective effects with attenuated neuroinflammation, reduced astrogliosis and improved functional recovery six weeks after severe contusion/compression SCI.

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