|
|
||||||||
Journal of Neurophysiology, Vol 70, Issue 2 803-813, Copyright © 1993 by APS
ARTICLES |
Y. Sqalli-Houssaini, J. R. Cazalets and F. Clarac
Centre National de la Recherche Scientifique, Laboratoire de Neurobiologie et Mouvement, Marseille, France.
1. The oscillatory properties of the lumbar spinal networks that generate locomotor activity in mammals were studied. These experiments were performed on an in vitro isolated spinal cord preparation from newborn rats. Adding to the saline serotonin (5-HT) and N-methyl-D-aspartate (NMDA) excitatory amino acid receptor agonist (N-methyl-D,L-aspartate, NMA) induced rhythmic locomotor-like activity that was recorded in the ventral roots. 2. The period of the rhythmic locomotor-like activity could be set by combining the neurotransmitters at various concentrations. The combined transmitters also acted on the instantaneous variations of the period value. The stability of the period from one cycle to another increased when 5-HT was mixed with NMA compared with the activity induced by bath application of the compound alone. 3. K(+)-induced depolarizations were used to set the neuron membrane potential. These systematic changes in the K+ concentration resulted in a change in the period value. 4. Stimulation of the dorsal roots reset the ongoing rhythm. Phase-response curves were drawn up that showed that the spinal networks exhibit a differential sensitivity to the same stimulus depending on the phase at which the stimulus is applied. The free-running activity could be entrained by the cyclic volleys of sensory discharges. Entrainment occurred, on average, between -28 and 36% of the rest period. Because the lumbar segments were completely isolated by means of a sucrose blockade of all descending neuronal activity, the entrainment of the locomotor activity must take place directly at the lumbar level. 5. In conclusion, our data show that, at birth, the rhythmic activity produced by the spinal networks is based on a neuronal architecture that displays oscillatory properties. At this early age, the peripheral sensory afferents have already established connections with the central pattern generator. These sensory inputs are able to control the cycling activity of the spinal networks step by step.
This article has been cited by other articles:
![]() |
G. Barriere, M. Tartas, J.-R. Cazalets, and S. S. Bertrand Interplay between neuromodulator-induced switching of short-term plasticity at sensorimotor synapses in the neonatal rat spinal cord J. Physiol., April 1, 2008; 586(7): 1903 - 1920. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Tazerart, J.-C. Viemari, P. Darbon, L. Vinay, and F. Brocard Contribution of Persistent Sodium Current to Locomotor Pattern Generation in Neonatal Rats J Neurophysiol, August 1, 2007; 98(2): 613 - 628. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Falgairolle and J.-R. Cazalets Metachronal coupling between spinal neuronal networks during locomotor activity in newborn rat J. Physiol., April 1, 2007; 580(1): 87 - 102. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. C. Cowley, E. Zaporozhets, J. N. MacLean, and B. J. Schmidt Is NMDA Receptor Activation Essential for the Production of Locomotor-Like Activity in the Neonatal Rat Spinal Cord? J Neurophysiol, December 1, 2005; 94(6): 3805 - 3814. [Abstract] [Full Text] [PDF] |
||||
![]() |
J.-R. Cazalets Metachronal propagation of motoneurone burst activation in isolated spinal cord of newborn rat J. Physiol., October 15, 2005; 568(2): 583 - 597. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. J. Christie and P. J. Whelan Monoaminergic Establishment of Rostrocaudal Gradients of Rhythmicity in the Neonatal Mouse Spinal Cord J Neurophysiol, August 1, 2005; 94(2): 1554 - 1564. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. A. Madriaga, L. C. McPhee, T. Chersa, K. J. Christie, and P. J. Whelan Modulation of Locomotor Activity by Multiple 5-HT and Dopaminergic Receptor Subtypes in the Neonatal Mouse Spinal Cord J Neurophysiol, September 1, 2004; 92(3): 1566 - 1576. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Giroux, C. Chau, H. Barbeau, T. A. Reader, and S. Rossignol Effects of Intrathecal Glutamatergic Drugs on Locomotion. II. NMDA and AP-5 in Intact and Late Spinal Cats J Neurophysiol, August 1, 2003; 90(2): 1027 - 1045. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. N. MacLean and B. J. Schmidt Voltage-Sensitivity of Motoneuron NMDA Receptor Channels Is Modulated by Serotonin in the Neonatal Rat Spinal Cord J Neurophysiol, September 1, 2001; 86(3): 1131 - 1138. [Abstract] [Full Text] [PDF] |
||||
![]() |
J.-R. Cazalets, M. Gardette, and G. Hilaire Locomotor Network Maturation Is Transiently Delayed in the MAOA-Deficient Mouse J Neurophysiol, April 1, 2000; 83(4): 2468 - 2470. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. C. Tresch and O. Kiehn Coding of Locomotor Phase in Populations of Neurons in Rostral and Caudal Segments of the Neonatal Rat Lumbar Spinal Cord J Neurophysiol, December 1, 1999; 82(6): 3563 - 3574. [Abstract] [Full Text] [PDF] |
||||
![]() |
O. Kiehn, K. T. Sillar, O. Kjaerulff, and J. R. McDearmid Effects of Noradrenaline on Locomotor Rhythm-Generating Networks in the Isolated Neonatal Rat Spinal Cord J Neurophysiol, August 1, 1999; 82(2): 741 - 746. [Abstract] [Full Text] [PDF] |
||||
![]() |
J.-R. CAZALETS, S. BERTRAND, Y. SQALLI-HOUSSAINI, and F. CLARAC Gabaergic Control of Spinal Locomotor Networks in the Neonatal Rat Ann. N.Y. Acad. Sci., November 16, 1998; 860(1): 168 - 180. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. J. SCHMIDT, S. HOCHMAN, and J. N. MacLEAN NMDA Receptor-mediated Oscillatory Properties: Potential Role in Rhythm Generation in the Mammalian Spinal Cord Ann. N.Y. Acad. Sci., November 16, 1998; 860(1): 189 - 202. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. KUDO and H. NISHIMARU Reorganization of Locomotor Activity during Development in the Prenatal Rat Ann. N.Y. Acad. Sci., November 16, 1998; 860(1): 306 - 317. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Raastad, M. Enriquez-Denton, and O. Kiehn Synaptic signaling in an active central network only moderately changes passive membrane properties PNAS, August 18, 1998; 95(17): 10251 - 10256. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. Kremer and A. Lev-Tov GABA-Receptor-Independent Dorsal Root Afferents Depolarization in the Neonatal Rat Spinal Cord J Neurophysiol, May 1, 1998; 79(5): 2581 - 2592. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. Bracci, M. Beato, and A. Nistri Extracellular K+ Induces Locomotor-Like Patterns in the Rat Spinal Cord In Vitro: Comparison With NMDA or 5-HT Induced Activity J Neurophysiol, May 1, 1998; 79(5): 2643 - 2652. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Hochman and B. J. Schmidt Whole Cell Recordings of Lumbar Motoneurons During Locomotor-Like Activity in the In Vitro Neonatal Rat Spinal Cord J Neurophysiol, February 1, 1998; 79(2): 743 - 752. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Bertrand and J.-R. Cazalets Postinhibitory Rebound During Locomotor-Like Activity in Neonatal Rat Motoneurons In Vitro J Neurophysiol, January 1, 1998; 79(1): 342 - 351. [Abstract] [Full Text] [PDF] |
||||
![]() |
O. Kjaerulff and O. Kiehn Crossed Rhythmic Synaptic Input to Motoneurons during Selective Activation of the Contralateral Spinal Locomotor Network J. Neurosci., December 15, 1997; 17(24): 9433 - 9447. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. Bracci, M. Beato, and A. Nistri Afferent Inputs Modulate the Activity of a Rhythmic Burst Generator in the Rat Disinhibited Spinal Cord In Vitro J Neurophysiol, June 1, 1997; 77(6): 3157 - 3167. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. R. Green, C. A. Moore, J. L. Ruark, P. R. Rodda, W. T. Morvee, and M. J. Vanwitzenburg Development of Chewing in Children From 12 to 48 Months: Longitudinal Study of EMG Patterns J Neurophysiol, May 1, 1997; 77(5): 2704 - 2716. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. Kremer and A. Lev-Tov Localization of the Spinal Network Associated With Generation of Hindlimb Locomotion in the Neonatal Rat and Organization of Its Transverse Coupling System J Neurophysiol, March 1, 1997; 77(3): 1155 - 1170. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. C. Cowley and B. J. Schmidt Regional Distribution of the Locomotor Pattern-Generating Network in the Neonatal Rat Spinal Cord J Neurophysiol, January 1, 1997; 77(1): 247 - 259. [Abstract] [Full Text] [PDF] |
||||
![]() |
O. Kjaerulff and O. Kiehn Distribution of Networks Generating and Coordinating Locomotor Activity in the Neonatal Rat Spinal Cord In Vitro: A Lesion Study J. Neurosci., September 15, 1996; 16(18): 5777 - 5794. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |