| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Center for Research in Neurological Sciences, Faculty of Medicine, Université de Montréal, Montreal, Quebec H3C 3J7 Canada
Carrier, Lynda, Edna Brustein, and Serge Rossignol. Locomotion of the hindlimbs after neurectomy of ankle flexors in intact and spinal cats: a model for the study of locomotor plasticity. J. Neurophysiol. 77: 1979-1993, 1997. To study the potential plasticity of locomotor networks in the spinal cord, an important issue for locomotor rehabilitation after spinal injuries, we have investigated the locomotor performance of cats before and after a unilateral denervation of the ankle flexors tibialis anterior (TA) and extensor digitorum longus (EDL) both in cats with intact spinal cord and after spinalization. The effects of the inactivation of the ankle flexors were studied in three cats with intact spinal cord during periods of 4-7 wk. Cats adapted their locomotor performance very rapidly within a few days so that the locomotor behavior appeared to be unchanged practically. However, kinematic analyses of video records often revealed small but consistent increase in knee and/or hip flexion. These changes were accompanied by some increase in the amplitude of knee and hip flexor muscle activity. Cats maintained a regular and symmetrical walking pattern over the treadmill for several minutes. Two of these cats then were spinalized at T13 and studied for ~1 mo afterward. Whereas normally cats regain a regular and symmetrical locomotor pattern after spinalization, these cats had a disorganized and asymmetrical locomotor pattern with a predominance of knee flexion and absence of plantar foot contact of the denervated limb. Another cat first was spinalized and allowed to recuperate a regular symmetrical locomotor performance. Then it also was submitted to the same unilateral ankle flexor inactivation and studied for ~50 days. The cat maintained a well-organized symmetrical gait although there was almost no ankle flexion on the denervated side. There was no exaggerated knee hyperflexion and gait asymmetry as seen in the two previous cats spinalized only after they had adapted to the denervation of ankle flexors. It is concluded that, after muscle denervation, locomotor adaptation is achieved through changes occurring at different levels. Because cats spinalized after adaptation to the neurectomy had an asymmetrical locomotor pattern dominated by hyperflexion, it is suggested that the spinal circuitry has been modified during the adaptive process, presumably through the action of corrective supraspinal inputs. Indeed spinal cats do not normally display such abnormal hyperflexions, and neither did the one cat denervated after spinalization. On the other hand, because the modified locomotor pattern in the spinal state is not functional and contains only some aspects of the compensatory response seen before spinalization, it is suggested that the complete functional adaptation observed in intact cats after peripheral nerve lesions may depend on changes occurring at the spinal and the supraspinal levels.
This article has been cited by other articles:
|
|
 |
|
  A. Frigon and S. Rossignol Plasticity of Reflexes From the Foot During Locomotion After Denervating Ankle Extensors in Intact Cats J Neurophysiol, October 1, 2007; 98(4): 2122 - 2132. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. A. McVea and K. G. Pearson Long-Lasting, Context-Dependent Modification of Stepping in the Cat After Repeated Stumbling-Corrective Responses J Neurophysiol, January 1, 2007; 97(1): 659 - 669. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. R. Wolpaw and X. Y. Chen The cerebellum in maintenance of a motor skill: A hierarchy of brain and spinal cord plasticity underlies H-reflex conditioning. Learn. Mem., March 1, 2006; 13(2): 208 - 215. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Rossignol, R. Dubuc, and J.-P. Gossard Dynamic Sensorimotor Interactions in Locomotion Physiol Rev, January 1, 2006; 86(1): 89 - 154. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. Bretzner and T. Drew Changes in Corticospinal Efficacy Contribute to the Locomotor Plasticity Observed After Unilateral Cutaneous Denervation of the Hindpaw in the Cat J Neurophysiol, October 1, 2005; 94(4): 2911 - 2927. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Y. Chen, X. Y. Chen, L. B. Jakeman, G. Schalk, B. T. Stokes, and J. R. Wolpaw The Interaction of a New Motor Skill and an Old One: H-Reflex Conditioning and Locomotion in Rats J. Neurosci., July 20, 2005; 25(29): 6898 - 6906. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
X. Y. Chen and J. R. Wolpaw Ablation of cerebellar nuclei prevents H-reflex down-conditioning in rats Learn. Mem., May 1, 2005; 12(3): 248 - 254. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Rossignol and L. Bouyer Adaptive Mechanisms of Spinal Locomotion in Cats Integr. Comp. Biol., February 1, 2004; 44(1): 71 - 79. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L.J.G. Bouyer and S. Rossignol Contribution of Cutaneous Inputs From the Hindpaw to the Control of Locomotion. II. Spinal Cats J Neurophysiol, December 1, 2003; 90(6): 3640 - 3653. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Y. C. Pang, T. Lam, and J. F. Yang Infants Adapt Their Stepping to Repeated Trip-Inducing Stimuli J Neurophysiol, October 1, 2003; 90(4): 2731 - 2740. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Lam, C. Wolstenholme, and J. F. Yang How Do Infants Adapt to Loading of the Limb During the Swing Phase of Stepping? J Neurophysiol, April 1, 2003; 89(4): 1920 - 1928. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Schneider and C. Capaday Progressive Adaptation of the Soleus H-Reflex With Daily Training at Walking Backward J Neurophysiol, February 1, 2003; 89(2): 648 - 656. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Yakovenko, V. Mushahwar, V. VanderHorst, G. Holstege, and A. Prochazka Spatiotemporal Activation of Lumbosacral Motoneurons in the Locomotor Step Cycle J Neurophysiol, March 1, 2002; 87(3): 1542 - 1553. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
X. Y. Chen and J. R. Wolpaw Probable Corticospinal Tract Control of Spinal Cord Plasticity in the Rat J Neurophysiol, February 1, 2002; 87(2): 645 - 652. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. E. Misiaszek and K. G. Pearson Adaptive Changes in Locomotor Activity Following Botulinum Toxin Injection in Ankle Extensor Muscles of Cats J Neurophysiol, January 1, 2002; 87(1): 229 - 239. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. MacKay-Lyons Central Pattern Generation of Locomotion: A Review of the Evidence Physical Therapy, January 1, 2002; 82(1): 69 - 83. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. M. Johnson and G. S. Mitchell Activity-Dependent Plasticity of Descending Synaptic Inputs to Spinal Motoneurons in an In Vitro Turtle Brainstem-Spinal Cord Preparation J. Neurosci., May 1, 2000; 20(9): 3487 - 3495. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. G. Pearson, K. Fouad, and J. E. Misiaszek Adaptive Changes in Motor Activity Associated With Functional Recovery Following Muscle Denervation in Walking Cats J Neurophysiol, July 1, 1999; 82(1): 370 - 381. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. Brustein and S. Rossignol Recovery of Locomotion After Ventral and Ventrolateral Spinal Lesions in the Cat. I. Deficits and Adaptive Mechanisms J Neurophysiol, September 1, 1998; 80(3): 1245 - 1267. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Chau, H. Barbeau, and S. Rossignol Early Locomotor Training With Clonidine in Spinal Cats J Neurophysiol, January 1, 1998; 79(1): 392 - 409. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
