 |
Previous Article | Next Article 
The Journal of Neuroscience, March 15, 2000, 20(6):2073-2085
Heterogeneous Conductance Levels of Native AMPA Receptors
T. Caitlin
Smith1,
Lu-Yang
Wang2, and
James R.
Howe1, 2
1 Interdepartmental Neuroscience Program and
2 Department of Pharmacology, Yale University School of
Medicine, New Haven, Connecticut 06520-8066
The single-channel properties of AMPA receptors can affect
information processing in neurons by influencing the amplitude and
kinetics of synaptic currents, yet little is known about the unitary
properties of native AMPA receptors in situ. Using
whole-cell and outside-out patch-clamp recordings from granule cells in
acute cerebellar slices, we found that migrating granule cells begin to
express AMPA receptors before they arrive in the internal granule cell
layer and receive synaptic input. At saturating agonist concentrations, the open probability of channels in outside-out patches from migrating cells was very high, allowing us to identify patches that contained only one or two active channels. Analysis of the single-channel activity in these patches showed that individual AMPA receptors exhibit
as many as four distinguishable conductance levels. The conductance
levels observed varied substantially for different channels, although
on average the values fell within the range of unitary conductances
estimated previously for synaptic AMPA receptors. In contrast to
patches from migrating granule cells, we rarely observed directly
resolvable single-channel currents in patches excised from the somata
of granule cells in the internal granular layer, even though these
cells gave large AMPA receptor whole-cell currents. We did, however,
detect AMPA receptors with apparent unitary conductances of <1 pS in
patches from both migrating and mature granule cells. Our results
suggest that granule cells express a heterogeneous population of AMPA
receptors, a subset of which are segregated to postsynaptic sites after synaptogenesis.
Key words:
granule cell; cerebellum; AMPA receptor; glutamate; single channel; synaptic; extrasynaptic; development
Copyright © 2000 Society for Neuroscience 0270-6474/00/2062073-13$05.00/0
This article has been cited by other articles:

|
 |

|
 |
 
W. Zhang, Y. Cho, E. Lolis, and J. R. Howe
Structural and Single-Channel Results Indicate That the Rates of Ligand Binding Domain Closing and Opening Directly Impact AMPA Receptor Gating
J. Neurosci.,
January 23, 2008;
28(4):
932 - 943.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
D. A. DiGregorio, J. S. Rothman, T. A. Nielsen, and R. A. Silver
Desensitization Properties of AMPA Receptors at the Cerebellar Mossy Fiber Granule Cell Synapse
J. Neurosci.,
August 1, 2007;
27(31):
8344 - 8357.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. Postlethwaite, M. H. Hennig, J. R. Steinert, B. P. Graham, and I. D. Forsythe
Acceleration of AMPA receptor kinetics underlies temperature-dependent changes in synaptic strength at the rat calyx of Held
J. Physiol.,
February 15, 2007;
579(1):
69 - 84.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
Y. Zhang, N. Nayeem, M. H. Nanao, and T. Green
Interface Interactions Modulating Desensitization of the Kainate-Selective Ionotropic Glutamate Receptor Subunit GluR6
J. Neurosci.,
September 27, 2006;
26(39):
10033 - 10042.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
E. Hartveit and M. L. Veruki
Studying properties of neurotransmitter receptors by non-stationary noise analysis of spontaneous synaptic currents
J. Physiol.,
August 1, 2006;
574(3):
751 - 785.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
R. A. Nicoll, S. Tomita, and D. S. Bredt
Auxiliary Subunits Assist AMPA-Type Glutamate Receptors.
Science,
March 3, 2006;
311(5765):
1253 - 1256.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
K. Erreger, M. T. Geballe, S. M. Dravid, J. P. Snyder, D. J. A. Wyllie, and S. F. Traynelis
Mechanism of Partial Agonism at NMDA Receptors for a Conformationally Restricted Glutamate Analog
J. Neurosci.,
August 24, 2005;
25(34):
7858 - 7866.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
N. J. Bannister, T. A. Benke, J. Mellor, H. Scott, E. Gurdal, J. W. Crabtree, and J. T. R. Isaac
Developmental Changes in AMPA and Kainate Receptor-Mediated Quantal Transmission at Thalamocortical Synapses in the Barrel Cortex
J. Neurosci.,
May 25, 2005;
25(21):
5259 - 5271.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
A. Robert, N. Armstrong, J. E. Gouaux, and J. R. Howe
AMPA Receptor Binding Cleft Mutations That Alter Affinity, Efficacy, and Recovery from Desensitization
J. Neurosci.,
April 13, 2005;
25(15):
3752 - 3762.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
T. Vaithianathan, K. Matthias, B. Bahr, M. Schachner, V. Suppiramaniam, A. Dityatev, and C. Steinhauser
Neural Cell Adhesion Molecule-associated Polysialic Acid Potentiates {alpha}-Amino-3-hydroxy-5-methylisoxazole-4-propionic Acid Receptor Currents
J. Biol. Chem.,
November 12, 2004;
279(46):
47975 - 47984.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
R. M. Klein and J. R. Howe
Effects of the Lurcher Mutation on GluR1 Desensitization and Activation Kinetics
J. Neurosci.,
May 26, 2004;
24(21):
4941 - 4951.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
L. Cathala, S. Brickley, S. Cull-Candy, and M. Farrant
Maturation of EPSCs and Intrinsic Membrane Properties Enhances Precision at a Cerebellar Synapse
J. Neurosci.,
July 9, 2003;
23(14):
6074 - 6085.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
A. Robert and J. R. Howe
How AMPA Receptor Desensitization Depends on Receptor Occupancy
J. Neurosci.,
February 1, 2003;
23(3):
847 - 858.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S. H. Morkve, M. L. Veruki, and E. Hartveit
Functional characteristics of non-NMDA-type ionotropic glutamate receptor channels in AII amacrine cells in rat retina
J. Physiol.,
July 1, 2002;
542(1):
147 - 165.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
C. Schmauss and J. R. Howe
RNA Editing of Neurotransmitter Receptors in the Mammalian Brain
Sci. Signal.,
May 21, 2002;
2002(133):
pe26 - pe26.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
D. Bowie and G. D. Lange
Functional Stoichiometry of Glutamate Receptor Desensitization
J. Neurosci.,
May 1, 2002;
22(9):
3392 - 3403.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
A. Robert, S. N. Irizarry, T. E. Hughes, and J. R. Howe
Subunit Interactions and AMPA Receptor Desensitization
J. Neurosci.,
August 1, 2001;
21(15):
5574 - 5586.
[Abstract]
[Full Text]
[PDF]
|
 |
|
|

|