Autoradiographic study of ?1- and ?2-noradrenergic and serotonin1A receptors in the spinal cord of normal and chronically transected cats

Giroux, Nicole; Rossignol, Serge; Reader, Tomás A.

doi:10.1002/(sici)1096-9861(19990412)406:3<402::aid-cne8>3.0.co;2-f

Cited by 117 publications

(91 citation statements)

References 70 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For instance, hindlimb locomotion after complete and incomplete spinal lesions is increasingly dependent on the proper integration of sensory afferent inputs Steeves, 1995, 1997;Bouyer and Rossignol, 2003) and it has been proposed that a normalization of these inputs is required for the expression of spinal stepping (Cote et al, 2003;Cote and Gossard, 2004). However, changes in neuronal and synaptic properties (Heckmann et al, 2005) and in neuromodulatory systems intrinsic to the spinal cord (de Leon et al, 1999;Giroux et al, 1999Giroux et al, , 2003Chau et al, 2002;Edgerton et al, 1997;Tillakaratne et al, 2002), are undoubtedly also involved.…”

Section: Reorganization Of the Spinal Locomotor Network After Partialmentioning

confidence: 83%

Prominent Role of the Spinal Central Pattern Generator in the Recovery of Locomotion after Partial Spinal Cord Injuries

Barrière¹,

Leblond²,

Provencher³

et al. 2008

J. Neurosci.

192

138

View full text Add to dashboard Cite

The re-expression of hindlimb locomotion after complete spinal cord injuries (SCIs) is caused by the presence of a spinal central pattern generator (CPG) for locomotion. After partial SCI, however, the role of this spinal CPG in the recovery of hindlimb locomotion in the cat remains mostly unknown. In the present work, we devised a dual-lesion paradigm to determine its possible contribution after partial SCI. After a partial section of the left thoracic segment T10 or T11, cats gradually recovered voluntary quadrupedal locomotion. Then, a complete transection was performed two to three segments more caudally (T13-L1) several weeks after the first partial lesion. Cats that received intensive treadmill training after the partial lesion expressed bilateral hindlimb locomotion within hours of the complete lesion. Untrained cats however showed asymmetrical hindlimb locomotion with the limb on the side of the partial lesion walking well before the other hindlimb. Thus, the complete spinalization revealed that the spinal CPG underwent plastic changes after the partial lesions, which were shaped by locomotor training. Over time, with further treadmill training, the asymmetry disappeared and a bilateral locomotion was reinstated. Therefore, although remnant intact descending pathways must contribute to voluntary goal-oriented locomotion after partial SCI, the recovery and re-expression of the hindlimb locomotor pattern mostly results from intrinsic changes below the lesion in the CPG and afferent inputs.

show abstract

Section: Reorganization Of the Spinal Locomotor Network After Partialmentioning

confidence: 83%

Prominent Role of the Spinal Central Pattern Generator in the Recovery of Locomotion after Partial Spinal Cord Injuries

Barrière¹,

Leblond²,

Provencher³

et al. 2008

J. Neurosci.

192

138

View full text Add to dashboard Cite

show abstract

“…24 Other transmembranal changes such as increased expression of subsets of serotonin, noradrenaline, glutamate and glycine receptors have also been proposed as factors that may contribute to functional recovery in Tx animals. [25][26][27] Why would performances 'level off' after 2-3 weeks with most assessment methods? It is clear that small recovery levels such as those seen in this animal model, which are characterized mainly by small amplitude movements, can rarely reach BBB scores above level 1 or 2.…”

Section: Discussionmentioning

confidence: 99%

Spontaneous recovery of hindlimb movement in completely spinal cord transected mice: a comparison of assessment methods and conditions

et al. 2006

View full text Add to dashboard Cite

Study design: To compare results obtained with a variety of locomotor rating scales in Th9/10 spinal cord transected (Tx) mice. Objectives: To assess spontaneous recovery with a variety of rating scales to find the most sensitive methods for assessing recovery levels in Tx mice and differences associated with gender and condition. Setting: Laval University Medical Center, Neuroscience Unit & Laval University, Department of Anatomy and Physiology, Quebec City, Quebec, Canada. Methods: Scales including the Basso, Beattie and Bresnahan (BBB), the Basso Mouse Score (BMS), the Antri, Orsal and Barthe (AOB), the Motor Function Score (MFS) and the Averaged Combined Score (ACOS) were used to assess, in open-field and treadmill conditions, spontaneous locomotor recovery in male and female Tx mice. Results: The ACOS scale revealed a progressive increase of spontaneous recovery during 5-weeks post-Tx. The other methods detected a progressive increase for the first 2-3 weeks postTx without any significant progress in weeks 4 and 5. Generally, scores obtained with each method were nonsignificantly different between males and females or between open-field and treadmill conditions. Conclusion: These results further confirm the existence of a limited but significant increase of locomotor function recovery, occurring without intervention, in Tx animals. Although each method could detect small levels of recovery, the ACOS method was discriminative enough to detect progressive changes up to 5 weeks post-Tx. In conclusion, the ACOS rating scale was the most discriminative method for assessing the spontaneous return of hindlimb movements found in Tx mice, both in open-field and treadmill conditions.

show abstract

“…Finally, biochemical plasticity involving neurotransmitters, receptor levels, and overall synaptic efficacy throughout the spinal cord occurs progressively over time, both in response to SCI [24,32], and to subsequent motor training [14,34]. For example, sprouting of peripheral fibers has been noted after SCI [29], likely impacting nociception [33], autonomic function [28,37], and proprioception [17].…”

Section: Potential Role Of State-dependent Spinal Plasticity In Acutementioning

confidence: 99%

“…For example, sprouting of peripheral fibers has been noted after SCI [29], likely impacting nociception [33], autonomic function [28,37], and proprioception [17]. Multiple studies have begun to elucidate a role for plasticity in various neurotransmitter systems in the lumbar spinal cord after SCI and how those changes relate to changes in motor performance [14,24,32,34]. The reduced capacity of the StandTr contra hindlimb for instrumental learning thus may be indicative of state-dependent biochemical and synaptic changes within the spinal circuits that occurred as a direct result of chronic weight-bearing activity of the Stand-Tr ipsi hindlimb in stand trained rats.…”

Section: Potential Role Of State-dependent Spinal Plasticity In Acutementioning

confidence: 99%

Two chronic motor training paradigms differentially influence acute instrumental learning in spinally transected rats

Bigbee

Crown

Ferguson

et al. 2007

Behavioural Brain Research

View full text Add to dashboard Cite

The effect of two chronic motor training paradigms on the ability of the lumbar spinal cord to perform an acute instrumental learning task was examined in neonatally (postnatal day 5; P5) spinal cord transected (i.e., spinal) rats. At ∼P30, rats began either unipedal hindlimb stand training (Stand-Tr; 20-25 min/day, 5 days/wk), or bipedal hindlimb step training (Step-Tr; 20 min/day; 5 days/wk) for 7 wks. Non-trained spinal rats (Non-Tr) served as controls. After 7 wks all groups were tested on the flexor-biased instrumental learning paradigm. We hypothesized that 1) Step-Tr rats would exhibit an increased capacity to learn the flexor-biased task relative to Non-Tr subjects, as locomotion involves repetitive training of the tibialis anterior (TA), the ankle flexor whose activation is important for successful instrumental learning, and 2) Stand-Tr rats would exhibit a deficit in acute motor learning, as unipedal training activates the ipsilateral ankle extensors, but not flexors. Results showed no differences in acute learning potential between Non-Tr and Step-Tr rats, while the Stand-Tr group showed a reduced capacity to learn the acute task. Further investigation of the Stand-Tr group showed that, while both the ipsilateral and contralateral hindlimbs were significantly impaired in their acute learning potential, the contralateral, untrained hindlimbs exhibited significantly greater learning deficits. These results suggest that different types of chronic peripheral input may have a significant impact on the ability to learn a novel motor task, and demonstrate the potential for experiencedependent plasticity in the spinal cord in the absence of supraspinal connectivity.

show abstract

Autoradiographic study of ?1- and ?2-noradrenergic and serotonin1A receptors in the spinal cord of normal and chronically transected cats

Cited by 117 publications

References 70 publications

Prominent Role of the Spinal Central Pattern Generator in the Recovery of Locomotion after Partial Spinal Cord Injuries

Prominent Role of the Spinal Central Pattern Generator in the Recovery of Locomotion after Partial Spinal Cord Injuries

Spontaneous recovery of hindlimb movement in completely spinal cord transected mice: a comparison of assessment methods and conditions

Two chronic motor training paradigms differentially influence acute instrumental learning in spinally transected rats

Contact Info

Product

Resources

About