| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Journal of Neurophysiology, Vol 62, Issue 1 59-69, Copyright © 1989 by APS
ARTICLES |
J. T. Buchanan, S. Grillner, S. Cullheim and M. Risling
Nobel Institute for Neurophysiology, Karolinska Institute, Stockholm, Sweden.
1. In the in vitro preparation of the lamprey spinal cord, paired intracellular recordings of membrane potential were used to identify interneurons producing excitatory postsynaptic potentials (EPSPs) on myotomal motoneurons. 2. Seventy-nine interneurons (8.4% of all neuron-motoneuron pairs tested) elicited unitary EPSPs that followed one-for-one at short, constant latencies and were therefore considered monosynaptic according to conventional criteria. Evidence was obtained for selectivity and divergence of excitatory interneuron (EIN) outputs and for convergence of EIN input to motoneurons. 3. The neurotransmitter released by EINs may be an excitatory amino acid such as glutamate, because the EPSPs were depressed by antagonists of excitatory amino acids. 4. Intracellular dye injection revealed that EINs have small cell bodies (average 11 x 27 microns), transversely oriented dendrites, and thin (less than 3 microns) slowly conducting axons (0.7 m/s) that project caudally and ipsilaterally. One EIN exhibited a system of thin multi-branching axon collaterals with periodic swellings. Ultrastructurally, these swellings contained clear spherical vesicles, and they apposed postsynaptic membrane specializations. 5. During fictive locomotion, the membrane-potential oscillations of EINs were greater in amplitude than, but similar in shape and timing to, those of their postsynaptic motoneurons. EINs fired action potentials during fictive locomotion and contributed to the depolarization of motoneurons. 6. These interneurons are proposed to be a source of excitation to motoneurons and interneurons in the lamprey spinal cord, participating in motor activity including locomotion.
This article has been cited by other articles:
|
|
 |
|
  M. Huss, A. Lansner, P. Wallen, A. El Manira, S. Grillner, and J. H. Kotaleski Roles of Ionic Currents in Lamprey CPG Neurons: A Modeling Study J Neurophysiol, April 1, 2007; 97(4): 2696 - 2711. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. Parker and S. Bevan Modulation of Cellular and Synaptic Variability in the Lamprey Spinal Cord J Neurophysiol, January 1, 2007; 97(1): 44 - 56. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. F. Einum and J. T. Buchanan Spinobulbar Neurons in Lamprey: Cellular Properties and Synaptic Interactions J Neurophysiol, October 1, 2006; 96(4): 2042 - 2055. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. M. Wilson, R. Hartley, D. J. Maxwell, A. J. Todd, I. Lieberam, J. A. Kaltschmidt, Y. Yoshida, T. M. Jessell, and R. M. Brownstone Conditional Rhythmicity of Ventral Spinal Interneurons Defined by Expression of the Hb9 Homeodomain Protein J. Neurosci., June 15, 2005; 25(24): 5710 - 5719. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. Cangiano and S. Grillner Mechanisms of Rhythm Generation in a Spinal Locomotor Network Deprived of Crossed Connections: The Lamprey Hemicord J. Neurosci., January 26, 2005; 25(4): 923 - 935. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Bevan and D. Parker Metaplastic Facilitation and Ultrastructural Changes in Synaptic Properties Are Associated with Long-Term Modulation of the Lamprey Locomotor Network J. Neurosci., October 20, 2004; 24(42): 9458 - 9468. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. F. Einum and J. T. Buchanan Reticulospinal Neurons Receive Direct Spinobulbar Inputs During Locomotor Activity in Lamprey J Neurophysiol, September 1, 2004; 92(3): 1384 - 1390. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. Parker Activity-Dependent Feedforward Inhibition Modulates Synaptic Transmission in a Spinal Locomotor Network J. Neurosci., December 3, 2003; 23(35): 11085 - 11093. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. Svensson, S. Grillner, and D. Parker Synaptically Evoked Membrane Potential Oscillations Induced by Substance P in Lamprey Motor Neurons J Neurophysiol, January 1, 2002; 87(1): 113 - 121. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. Fagerstedt and F. Ullen Lateral Turns in the Lamprey. I. Patterns of Motoneuron Activity J Neurophysiol, November 1, 2001; 86(5): 2246 - 2256. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. V. Zelenin, S. Grillner, G. N. Orlovsky, and T. G. Deliagina Heterogeneity of the Population of Command Neurons in the Lamprey J. Neurosci., October 1, 2001; 21(19): 7793 - 7803. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. Tschuluun, W. M. Hall, and B. Mulloney Limb Movements during Locomotion: Tests of a Model of an Intersegmental Coordinating Circuit J. Neurosci., October 1, 2001; 21(19): 7859 - 7869. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Buschges, M. A. Wikstrom, S. Grillner, and A. El Manira Roles of High-Voltage-Activated Calcium Channel Subtypes in a Vertebrate Spinal Locomotor Network J Neurophysiol, December 1, 2000; 84(6): 2758 - 2766. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. C. Rekling, G. D. Funk, D. A. Bayliss, X.-W. Dong, and J. L. Feldman Synaptic Control of Motoneuronal Excitability Physiol Rev, April 1, 2000; 80(2): 767 - 852. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. Parker Activity and Calcium-Dependent Mechanisms Maintain Reliable Interneuron Synaptic Transmission in a Rhythmic Neural Network J. Neurosci., March 1, 2000; 20(5): 1754 - 1766. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. L. Miller and K. A. Sigvardt Extent and Role of Multisegmental Coupling in the Lamprey Spinal Locomotor Pattern Generator J Neurophysiol, January 1, 2000; 83(1): 465 - 476. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. T. Buchanan and S. Kasicki Segmental Distribution of Common Synaptic Inputs to Spinal Motoneurons During Fictive Swimming in the Lamprey J Neurophysiol, September 1, 1999; 82(3): 1156 - 1163. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. T. Buchanan Commissural Interneurons in Rhythm Generation and Intersegmental Coupling in the Lamprey Spinal Cord J Neurophysiol, May 1, 1999; 81(5): 2037 - 2045. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. GRILLNER, D. PARKER, and A. EL MANIRA Vertebrate Locomotion-A Lamprey Perspective Ann. N.Y. Acad. Sci., November 16, 1998; 860(1): 1 - 18. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. A. SIGVARDT and W. L. MILLER Analysis and Modeling of the Locomotor Central Pattern Generator as a Network of Coupled Oscillators Ann. N.Y. Acad. Sci., November 16, 1998; 860(1): 250 - 265. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. Parker and S. Grillner Cellular and Synaptic Modulation Underlying Substance P-Mediated Plasticity of the Lamprey Locomotor Network J. Neurosci., October 1, 1998; 18(19): 8095 - 8110. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Tegner, J. Hellgren-Kotaleski, A. Lansner, and S. Grillner Low-Voltage-Activated Calcium Channels in the Lamprey Locomotor Network: Simulation and Experiment J Neurophysiol, April 1, 1997; 77(4): 1795 - 1812. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
