JN Watch the video to learn how APS reaches out to developing nations.
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

J Neurophysiol 86: 1006-1016, 2001;
0022-3077/01 $5.00
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via ISI Web of Science (15)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Koizumi, A.
Right arrow Articles by Kaneko, A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Koizumi, A.
Right arrow Articles by Kaneko, A.

The Journal of Neurophysiology Vol. 86 No. 2 August 2001, pp. 1006-1016
Copyright ©2001 by the American Physiological Society

Persistent Na+ Current and Ca2+ Current Boost Graded Depolarization of Rat Retinal Amacrine Cells in Culture

Amane Koizumi, Shu-Ichi Watanabe, and Akimichi Kaneko

Department of Physiology, Keio University School of Medicine, Tokyo 160-8582, Japan

Koizumi, Amane, Shu-Ichi Watanabe, and Akimichi Kaneko. Persistent Na+ Current and Ca2+ Current Boost Graded Depolarization of Rat Retinal Amacrine Cells in Culture. J. Neurophysiol. 86: 1006-1016, 2001. Retinal amacrine cells are depolarized by the excitatory synaptic input from bipolar cells. When a graded depolarization exceeds the threshold level, trains of action potentials are generated. There have been several reports that both spikes and graded depolarization are sensitive to tetrodotoxin (TTX). In the present study, we investigated the contribution of voltage-gated currents to membrane depolarization by using rat GABAergic amacrine cells in culture recorded by the patch-clamp method. Injection of a negative current induced membrane hyperpolarization, the waveform of which can be well fitted by a single exponential function. Injection of positive current depolarized the cell, and the depolarization exceeded the amplitude expected from the passive properties of the membrane. The boosted depolarization sustained after the current was turned off. Either 1 µM TTX or 2 mM Co2+ suppressed the boosted depolarization, and co-application of TTX and Co2+ blocked it completely. Under the voltage clamp, we identified a transient Na+ current (fast INa), a TTX-sensitive persistent current that reversed the polarity near the equilibrium potential of Na+ (INaP), and three types of Ca2+ currents (ICa), L, N, and the pharmacological agent-resistant type (R type). These findings suggest that the INaP and ICa of amacrine cells boost depolarization evoked by the excitatory synaptic input, and they may aid the spread of electrical signals among dendritic arbors of amacrine cells.




This article has been cited by other articles:


Home page
 J. Physiol.Home page
M. L. Veruki, S. B. Gill, and E. Hartveit
Spontaneous IPSCs and glycine receptors with slow kinetics in wide-field amacrine cells in the mature rat retina
J. Physiol., May 15, 2007; 581(1): 203 - 219.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurosci.Home page
J. Vigh and H. von Gersdorff
Prolonged Reciprocal Signaling via NMDA and GABA Receptors at a Retinal Ribbon Synapse
J. Neurosci., December 7, 2005; 25(49): 11412 - 11423.
[Abstract] [Full Text] [PDF]

Home page
 Biophys. JHome page
M. A. Steffen, C. A. Seay, B. Amini, Y. Cai, A. Feigenspan, D. A. Baxter, and D. W. Marshak
Spontaneous Activity of Dopaminergic Retinal Neurons
Biophys. J., October 1, 2003; 85(4): 2158 - 2169.
[Abstract] [Full Text] [PDF]

Home page
 J. Gen. Physiol.Home page
K. Djupsund, T. Furukawa, S. Yasui, and M. Yamada
Asymmetric Temporal Properties in the Receptive Field of Retinal Transient Amacrine Cells
J. Gen. Physiol., September 29, 2003; 122(4): 445 - 458.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurosci.Home page
C. J. Habermann, B. J. O'Brien, H. Wassle, and D. A. Protti
AII Amacrine Cells Express L-Type Calcium Channels at Their Output Synapses
J. Neurosci., July 30, 2003; 23(17): 6904 - 6913.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurophysiol.Home page
C. R. Shields and P. D. Lukasiewicz
Spike-Dependent GABA Inputs to Bipolar Cell Axon Terminals Contribute to Lateral Inhibition of Retinal Ganglion Cells
J Neurophysiol, May 1, 2003; 89(5): 2449 - 2458.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurosci.Home page
K. J. Kim and F. Rieke
Slow Na+ Inactivation and Variance Adaptation in Salamander Retinal Ganglion Cells
J. Neurosci., February 15, 2003; 23(4): 1506 - 1516.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurophysiol.Home page
Y. Yamada, A. Koizumi, E. Iwasaki, S.-I. Watanabe, and A. Kaneko
Propagation of Action Potentials From the Soma to Individual Dendrite of Cultured Rat Amacrine Cells Is Regulated by Local GABA Input
J Neurophysiol, June 1, 2002; 87(6): 2858 - 2866.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online