Cerebral Cortex, Vol. 9, No. 8, 833-843,
December 1999
© 1999 Oxford University Press
Intracortical Excitation of Spiny Neurons in Layer 4 of Cat Striate Cortex In Vitro
University Laboratory of Physiology, Parks Road, Oxford OX1 3PT, UK and , 1 Institute of Neuroinformatics, University/ETH Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
Address correspondence to K.A.C. Martin, Institute of Neuroinformatics, University/ETH Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland. Email : kevan{at}ini.phys.ethz.ch.
Recordings were made from pairs of neurons in cat striate visual cortex in vitro to study the AMPA-channel-mediated components of intracortical excitatory synaptic connections between layer 4 spiny neurons and between layer 6 and layer 4 spiny neurons. Forty-six of the 72 cells recorded were identified morphologically. They consisted of spiny stellate and pyramidal cells in layer 4, and pyramidal cells in layer 6. Connections between layer 4 excitatory cells involve excitatory postsynaptic potentials (EPSPs) averaging 949 µV, with an average coefficient of variation of 0.21 (n = 30). The synapses operate at very high release probabilities (0.690.98). With repetitive stimulation these EPSPs show varying degrees of depression, largely mediated by presynaptic changes in release probability. Four pairs of layer 4 cells were reciprocally connected. The connections from layer 6 to layer 4 involve smaller, more variable EPSPs, with an average amplitude of 214 µV, and average coefficient of variation 0.72 (n = 7). These synapses operate at moderately high release probabilities (0.370.56). They show facilitation with repetitive stimulation, mediated largely by presynaptic changes in release probability. One excitatory connection from a layer 4 neuron to a layer 6 pyramidal cell was also detected. Thus, layer 4 spiny neurons receive effective excitation from two intracortical sources that have different synaptic dynamics and are likely to contribute significantly to the temporal properties of these cells in vivo.
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
C. C. Lee and S. M. Sherman Synaptic Properties of Thalamic and Intracortical Inputs to Layer 4 of the First- and Higher-Order Cortical Areas in the Auditory and Somatosensory Systems J Neurophysiol, July 1, 2008; 100(1): 317 - 326. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. P. Bannister and A. M. Thomson Dynamic Properties of Excitatory Synaptic Connections Involving Layer 4 Pyramidal Cells in Adult Rat and Cat Neocortex Cereb Cortex, September 1, 2007; 17(9): 2190 - 2203. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Bremaud, D. C. West, and A. M. Thomson Binomial parameters differ across neocortical layers and with different classes of connections in adult rat and cat neocortex PNAS, August 28, 2007; 104(35): 14134 - 14139. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. B. Ali and C. Nelson Distinct Ca2+ Channels Mediate Transmitter Release at Excitatory Synapses Displaying Different Dynamic Properties in Rat Neocortex Cereb Cortex, March 1, 2006; 16(3): 386 - 393. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. C. West, A. Mercer, S. Kirchhecker, O. T. Morris, and A. M. Thomson Layer 6 Cortico-thalamic Pyramidal Cells Preferentially Innervate Interneurons and Generate Facilitating EPSPs Cereb Cortex, February 1, 2006; 16(2): 200 - 211. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. E. Boudreau and D. Ferster Short-Term Depression in Thalamocortical Synapses of Cat Primary Visual Cortex J. Neurosci., August 3, 2005; 25(31): 7179 - 7190. [Abstract] [Full Text] [PDF] |
||||
![]() |
O. Beck, M. Chistiakova, K. Obermayer, and M. Volgushev Adaptation at Synaptic Connections to Layer 2/3 Pyramidal Cells in Rat Visual Cortex J Neurophysiol, July 1, 2005; 94(1): 363 - 376. [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] |
||||
![]() |
D. Feldmeyer, A. Roth, and B. Sakmann Monosynaptic Connections between Pairs of Spiny Stellate Cells in Layer 4 and Pyramidal Cells in Layer 5A Indicate That Lemniscal and Paralemniscal Afferent Pathways Converge in the Infragranular Somatosensory Cortex J. Neurosci., March 30, 2005; 25(13): 3423 - 3431. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. I. Cowan and C. Stricker Functional Connectivity in Layer IV Local Excitatory Circuits of Rat Somatosensory Cortex J Neurophysiol, October 1, 2004; 92(4): 2137 - 2150. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Gonzalez-Burgos, L. S. Krimer, N. N. Urban, G. Barrionuevo, and D. A. Lewis Synaptic Efficacy during Repetitive Activation of Excitatory Inputs in Primate Dorsolateral Prefrontal Cortex Cereb Cortex, May 1, 2004; 14(5): 530 - 542. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. B. Wilent and D. Contreras Synaptic Responses to Whisker Deflections in Rat Barrel Cortex as a Function of Cortical Layer and Stimulus Intensity J. Neurosci., April 21, 2004; 24(16): 3985 - 3998. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Wirth and H.-R. Luscher Spatiotemporal Evolution of Excitation and Inhibition in the Rat Barrel Cortex Investigated With Multielectrode Arrays J Neurophysiol, April 1, 2004; 91(4): 1635 - 1647. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Kuhn, A. Aertsen, and S. Rotter Neuronal Integration of Synaptic Input in the Fluctuation-Driven Regime J. Neurosci., March 10, 2004; 24(10): 2345 - 2356. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Gonchar and A. Burkhalter Distinct GABAergic Targets of Feedforward and Feedback Connections Between Lower and Higher Areas of Rat Visual Cortex J. Neurosci., November 26, 2003; 23(34): 10904 - 10912. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Eyding, J. D. Macklis, U. Neubacher, K. Funke, and F. Worgotter Selective Elimination of Corticogeniculate Feedback Abolishes the Electroencephalogram Dependence of Primary Visual Cortical Receptive Fields and Reduces Their Spatial Specificity J. Neurosci., August 6, 2003; 23(18): 7021 - 7033. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. Granseth and S. Lindstrom Unitary EPSCs of Corticogeniculate Fibers in the Rat Dorsal Lateral Geniculate Nucleus In Vitro J Neurophysiol, June 1, 2003; 89(6): 2952 - 2960. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Schubert, R. Kotter, K. Zilles, H. J. Luhmann, and J. F. Staiger Cell Type-Specific Circuits of Cortical Layer IV Spiny Neurons J. Neurosci., April 1, 2003; 23(7): 2961 - 2970. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. M. Thomson and A. P. Bannister Interlaminar Connections in the Neocortex Cereb Cortex, January 1, 2003; 13(1): 5 - 14. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. C. H. Petersen Short-Term Dynamics of Synaptic Transmission Within the Excitatory Neuronal Network of Rat Layer 4 Barrel Cortex J Neurophysiol, June 1, 2002; 87(6): 2904 - 2914. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Fuhrmann, I. Segev, H. Markram, and M. Tsodyks Coding of Temporal Information by Activity-Dependent Synapses J Neurophysiol, January 1, 2002; 87(1): 140 - 148. [Abstract] [Full Text] [PDF] |
||||



