|
|
||||||||
Journal of Neurophysiology, Vol 48, Issue 6 1321-1335, Copyright © 1982 by APS
ARTICLES |
M. J. Gutnick, B. W. Connors and D. A. Prince
1. The cellular mechanisms underlying interictal epileptogenesis have been examined in an in vitro slice preparation of guinea pig neocortex. Penicillin or bicuculline was applied to the tissue, and intracellular recordings were obtained from neurons and glia. 2. Following convulsant application, stimulation could elicit a short-latency excitatory postsynaptic potential (EPSP) and a large, longer latency depolarization shift (DS) in single neurons. DSs in neurons of the slice were very similar to those evoked in neurons of neocortex in vivo in that they displayed an all-or-none character, large shifts in latency during repetitive stimuli, long afterpotentials, and a prolonged refractory period. In contrast to epileptogenesis produced by penicillin in intact cortex, neither spontaneous DSs nor ictal episodes were observed in neocortical slices. 3. In simultaneous recordings from pairs of neurons within the same cortical column, DS generation and latency shifts were invariably synchronous. DS generation in neurons was also coincident with large, paroxysmal increases of extracellular [K+], as indicated by simultaneous recordings from glia. 4. When polarizing currents were applied to neurons injected with the local anesthetic QX-314, the DS amplitude varied monotonically and had an extrapolated reversal potential near 0 mV. In neurons injected with the K+-current blocker Cs+, large displacements of membrane potential were possible, and both the short-latency EPSP and the peak of the DS diminished completely at about 0 mV. At potentials positive to this, the short-latency EPSP was reversed, and the DS was replaced by a paroxysmal hyperpolarization whose rise time and peak latency were prolonged compared to the DS evoked at resting potential. The paroxysmal hyperpolarization probably represents the prolonged activation of the impaled neuron by EPSPs. 5. Voltage-dependent components, including slow spikes, appeared to contribute to generation of the DS at resting potential in Cs+-filled cells, and these components were blocked during large depolarizations. 6. The results suggest that DS generation in single neocortical neurons occurs during synchronous synaptic activation of a large group of cells. DS onset in a given neuron is determined by the timing of a variable-latency excitatory input that differs from the short-latency EPSP. The DS slow envelope appears to be generated by long-duration excitatory synaptic currents and may be modulated by intrinsic voltage-dependent membrane conductances. 7. We present a hypothesis for the initiation of the DS, based on the anatomical and physiological organization of the intrinsic neocortical circuits.
This article has been cited by other articles:
![]() |
M. T. Lippert, K. Takagaki, W. Xu, X. Huang, and J.-Y. Wu Methods for Voltage-Sensitive Dye Imaging of Rat Cortical Activity With High Signal-to-Noise Ratio J Neurophysiol, July 1, 2007; 98(1): 502 - 512. [Abstract] [Full Text] [PDF] |
||||
![]() |
O. Feinerman, M. Segal, and E. Moses Identification and Dynamics of Spontaneous Burst Initiation Zones in Unidimensional Neuronal Cultures J Neurophysiol, April 1, 2007; 97(4): 2937 - 2948. [Abstract] [Full Text] [PDF] |
||||
![]() |
O. Feinerman, M. Segal, and E. Moses Signal Propagation Along Unidimensional Neuronal Networks J Neurophysiol, November 1, 2005; 94(5): 3406 - 3416. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. J. Pinto, S. L. Patrick, W. C. Huang, and B. W. Connors Initiation, Propagation, and Termination of Epileptiform Activity in Rodent Neocortex In Vitro Involve Distinct Mechanisms J. Neurosci., September 7, 2005; 25(36): 8131 - 8140. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. D. Traub, I. Pais, A. Bibbig, F. E.N. LeBeau, E. H. Buhl, H. Garner, H. Monyer, and M. A. Whittington Transient Depression of Excitatory Synapses on Interneurons Contributes to Epileptiform Bursts During Gamma Oscillations in the Mouse Hippocampal Slice J Neurophysiol, August 1, 2005; 94(2): 1225 - 1235. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. D. Traub, D. Contreras, M. O. Cunningham, H. Murray, F. E. N. LeBeau, A. Roopun, A. Bibbig, W. B. Wilent, M. J. Higley, and M. A. Whittington Single-Column Thalamocortical Network Model Exhibiting Gamma Oscillations, Sleep Spindles, and Epileptogenic Bursts J Neurophysiol, April 1, 2005; 93(4): 2194 - 2232. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Bandyopadhyay, C. Gonzalez-Islas, and J. J. Hablitz Dopamine Enhances Spatiotemporal Spread of Activity in Rat Prefrontal Cortex J Neurophysiol, February 1, 2005; 93(2): 864 - 872. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. Seiffert, J. P. Dreier, S. Ivens, I. Bechmann, O. Tomkins, U. Heinemann, and A. Friedman Lasting Blood-Brain Barrier Disruption Induces Epileptic Focus in the Rat Somatosensory Cortex J. Neurosci., September 8, 2004; 24(36): 7829 - 7836. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Bazhenov, I. Timofeev, M. Steriade, and T. J. Sejnowski Potassium Model for Slow (2-3 Hz) In Vivo Neocortical Paroxysmal Oscillations J Neurophysiol, August 1, 2004; 92(2): 1116 - 1132. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. van Drongelen, H. Koch, C. Marcuccilli, F. Pena, and J.-M. Ramirez Synchrony Levels During Evoked Seizure-Like Bursts in Mouse Neocortical Slices J Neurophysiol, September 1, 2003; 90(3): 1571 - 1580. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Laurent, J.-M. Goaillard, O. Cases, C. Lebrand, P. Gaspar, and N. Ropert Activity-Dependent Presynaptic Effect of Serotonin 1B Receptors on the Somatosensory Thalamocortical Transmission in Neonatal Mice J. Neurosci., February 1, 2002; 22(3): 886 - 900. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. van Vreeswijk and D. Hansel Patterns of Synchrony in Neural Networks with Spike Adaptation Neural Comput., May 1, 2001; 13(5): 959 - 992. [Abstract] [Full Text] |
||||
![]() |
B. N. Smith and F. E. Dudek Short- and Long-Term Changes in CA1 Network Excitability After Kainate Treatment in Rats J Neurophysiol, January 1, 2001; 85(1): 1 - 9. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. A. Castro-Alamancos Origin of Synchronized Oscillations Induced by Neocortical Disinhibition In Vivo J. Neurosci., December 15, 2000; 20(24): 9195 - 9206. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. E. Wells, J. T. Porter, and A. Agmon GABAergic Inhibition Suppresses Paroxysmal Network Activity in the Neonatal Rodent Hippocampus and Neocortex J. Neurosci., December 1, 2000; 20(23): 8822 - 8830. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. Sutor, C. Schmolke, B. Teubner, C. Schirmer, and K. Willecke Myelination Defects and Neuronal Hyperexcitability in the Neocortex of Connexin 32-deficient Mice Cereb Cortex, July 1, 2000; 10(7): 684 - 697. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Gonzalez-Burgos, G. Barrionuevo, and D. A. Lewis Horizontal Synaptic Connections in Monkey Prefrontal Cortex: An In Vitro Electrophysiological Study Cereb Cortex, January 1, 2000; 10(1): 82 - 92. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Steriade and F. Amzica Intracellular Study of Excitability in the Seizure-Prone Neocortex In Vivo J Neurophysiol, December 1, 1999; 82(6): 3108 - 3122. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Golomb and G. B. Ermentrout Continuous and lurching traveling pulses in neuronal networks with delay and spatially decaying connectivity PNAS, November 9, 1999; 96(23): 13480 - 13485. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. Golshani and E. G. Jones Synchronized Paroxysmal Activity in the Developing Thalamocortical Network Mediated by Corticothalamic Projections and "Silent" Synapses J. Neurosci., April 15, 1999; 19(8): 2865 - 2875. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. M. Jacobs, B. J. Hwang, and D. A. Prince Focal Epileptogenesis in a Rat Model of Polymicrogyria J Neurophysiol, January 1, 1999; 81(1): 159 - 173. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Steriade and D. Contreras Spike-Wave Complexes and Fast Components of Cortically Generated Seizures. I. Role of Neocortex and Thalamus J Neurophysiol, September 1, 1998; 80(3): 1439 - 1455. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. B. Colling, I. M. Stanford, R. D. Traub, and J. G. R. Jefferys Limbic Gamma Rhythms. I. Phase-Locked Oscillations in Hippocampal CA1 and Subiculum J Neurophysiol, July 1, 1998; 80(1): 155 - 161. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Golomb Models of Neuronal Transient Synchrony During Propagation of Activity Through Neocortical Circuitry J Neurophysiol, January 1, 1998; 79(1): 1 - 12. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. Lopantsev and M. Avoli Participation of GABAA-Mediated Inhibition in Ictallike Discharges in the Rat Entorhinal Cortex J Neurophysiol, January 1, 1998; 79(1): 352 - 360. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Golomb and Y. Amitai Propagating Neuronal Discharges in Neocortical Slices: Computational and Experimental Study J Neurophysiol, September 1, 1997; 78(3): 1199 - 1211. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. S. Lukatch and M. B. Maciver Physiology, Pharmacology, and Topography of Cholinergic Neocortical Oscillations In Vitro J Neurophysiol, May 1, 1997; 77(5): 2427 - 2445. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Silva, Y Amitai, and B. Connors Intrinsic oscillations of neocortex generated by layer 5 pyramidal neurons Science, January 25, 1991; 251(4992): 432 - 435. [Abstract] [PDF] |
||||
![]() |
M. Dichter and G. Ayala Cellular mechanisms of epilepsy: a status report Science, July 10, 1987; 237(4811): 157 - 164. [Abstract] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |