 |
||||
|
||||
|
||||
|
||||
.gif?ad=17923&adview=true)
Previous Article | Next Article
Volume 17, Number 19, Issue of October 1, 1997 pp. 7297-7306
Copyright ©1997 Society for NeuroscienceGain of Rod to Horizontal Cell Synaptic Transfer: Relation to Glutamate Release and a Dihydropyridine-Sensitive Calcium Current
Received March 25, 1997; revised June 2, 1997; accepted July 18, 1997.
Paul Witkovsky1, 2, Yvonne Schmitz1, Abram Akopian1, David Krizaj1, 2, and Daniel Tranchina3 Departments of 1 Ophthalmology and 2 Physiology and Neuroscience, New York University Medical Center, New York, New York 10016, and 3 Departments of Biology and Mathematics and the Center for Neural Science, New York University, New York, New York 10003
We related rod to horizontal cell synaptic transfer to glutamate release by rods. Simultaneous intracellular records were obtained from dark-adapted rod-horizontal cell pairs. Steady-state synaptic gain (defined as the ratio of horizontal cell voltage to rod voltage evoked by the same light stimulus) was 3.35 ± 0.60 for dim flashes and 1.50 ± 0.03 for bright flashes. Under conditions of maintained illumination, there was a measurable increment of horizontal cell hyperpolarization for each light-induced increment of rod hyperpolarization over the full range of rod voltages.
In separate experiments we studied glutamate release from an intact, light-responsive photoreceptor layer, from which inner retinal layers were removed. Steady light reduced glutamate release as a monotonic function of intensity; spectral sensitivity measures indicated that we monitored glutamate release from rods. The dependence of glutamate release on rod voltage was well fit by the activation function for a high-voltage-activated, dihydropyridine-sensitive L-type calcium current, suggesting a linear dependence of glutamate release on [Ca]i in the synaptic terminal. A simple model incorporating this assumption accounts for the steady-state gain of the rod to horizontal cell synapse.
Key words: Xenopus; photoreceptor; rod; synaptic gain; horizontal cell; glutamate release; calcium
This article has been cited by other articles:
J. Trumpler, K. Dedek, T. Schubert, L. P. de Sevilla Muller, M. Seeliger, P. Humphries, M. Biel, and R. Weiler
Rod and Cone Contributions to Horizontal Cell Light Responses in the Mouse Retina
J. Neurosci., July 2, 2008; 28(27): 6818 - 6825.
[Abstract] [Full Text] [PDF]
D. Reigada, W. Lu, and C. H. Mitchell
Glutamate acts at NMDA receptors on fresh bovine and on cultured human retinal pigment epithelial cells to trigger release of ATP
J. Physiol., September 15, 2006; 575(3): 707 - 720.
[Abstract] [Full Text] [PDF]
A. Suryanarayanan and M. M. Slaughter
Synaptic Transmission Mediated by Internal Calcium Stores in Rod Photoreceptors
J. Neurosci., February 8, 2006; 26(6): 1759 - 1766.
[Abstract] [Full Text] [PDF]
S. Schein and K. M. Ahmad
A Clockwork Hypothesis: Synaptic Release by Rod Photoreceptors Must Be Regular
Biophys. J., December 1, 2005; 89(6): 3931 - 3949.
[Abstract] [Full Text] [PDF]
J. W. Xu and M. M. Slaughter
Large-Conductance Calcium-Activated Potassium Channels Facilitate Transmitter Release in Salamander Rod Synapse
J. Neurosci., August 17, 2005; 25(33): 7660 - 7668.
[Abstract] [Full Text] [PDF]
A. Hemara-Wahanui, S. Berjukow, C. I. Hope, P. K. Dearden, S.-B. Wu, J. Wilson-Wheeler, D. M. Sharp, P. Lundon-Treweek, G. M. Clover, J.-C. Hoda, et al.
A CACNA1F mutation identified in an X-linked retinal disorder shifts the voltage dependence of Cav1.4 channel activation
PNAS, May 24, 2005; 102(21): 7553 - 7558.
[Abstract] [Full Text] [PDF]
J.-C. Hoda, F. Zaghetto, A. Koschak, and J. Striessnig
Congenital Stationary Night Blindness Type 2 Mutations S229P, G369D, L1068P, and W1440X Alter Channel Gating or Functional Expression of Cav1.4 L-type Ca2+ Channels
J. Neurosci., January 5, 2005; 25(1): 252 - 259.
[Abstract] [Full Text] [PDF]
A. Koschak, D. Reimer, D. Walter, J.-C. Hoda, T. Heinzle, M. Grabner, and J. Striessnig
Cav1.4{alpha}1 Subunits Can Form Slowly Inactivating Dihydropyridine-Sensitive L-Type Ca2+ Channels Lacking Ca2+-Dependent Inactivation
J. Neurosci., July 9, 2003; 23(14): 6041 - 6049.
[Abstract] [Full Text] [PDF]
C. E. Armstrong-Gold and F. Rieke
Bandpass Filtering at the Rod to Second-Order Cell Synapse in Salamander (Ambystoma tigrinum) Retina
J. Neurosci., May 1, 2003; 23(9): 3796 - 3806.
[Abstract] [Full Text] [PDF]
I. Nir, J. M. Harrison, R. Haque, M. J. Low, D. K. Grandy, M. Rubinstein, and P. M. Iuvone
Dysfunctional Light-Evoked Regulation of cAMP in Photoreceptors and Abnormal Retinal Adaptation in Mice Lacking Dopamine D4 Receptors
J. Neurosci., March 15, 2002; 22(6): 2063 - 2073.
[Abstract] [Full Text] [PDF]
K. Matsui, J. Hasegawa, and M. Tachibana
Modulation of Excitatory Synaptic Transmission by GABAC Receptor-Mediated Feedback in the Mouse Inner Retina
J Neurophysiol, November 1, 2001; 86(5): 2285 - 2298.
[Abstract] [Full Text] [PDF]
J. H. Singer, R. R. Mirotznik, and M. B. Feller
Potentiation of L-Type Calcium Channels Reveals Nonsynaptic Mechanisms that Correlate Spontaneous Activity in the Developing Mammalian Retina
J. Neurosci., November 1, 2001; 21(21): 8514 - 8522.
[Abstract] [Full Text] [PDF]
H. P. N. Scholl, H. Langrova, C. M. Pusch, B. Wissinger, E. Zrenner, and E. Apfelstedt-Sylla
Slow and Fast Rod ERG Pathways in Patients with X-Linked Complete Stationary Night Blindness Carrying Mutations in the NYX Gene
Invest. Ophthalmol. Vis. Sci., October 1, 2001; 42(11): 2728 - 2736.
[Abstract] [Full Text] [PDF]
R. Kurtz, A.-K. Warzecha, and M. Egelhaaf
Transfer of Visual Motion Information via Graded Synapses Operates Linearly in the Natural Activity Range
J. Neurosci., September 1, 2001; 21(17): 6957 - 6966.
[Abstract] [Full Text] [PDF]
D. A. Kraaij, H. Spekreijse, and M. Kamermans
The Open- and Closed-Loop Gain-Characteristics of the Cone/Horizontal Cell Synapse in Goldfish Retina
J Neurophysiol, September 1, 2000; 84(3): 1256 - 1265.
[Abstract] [Full Text] [PDF]
A. Akopian, J. Johnson, R. Gabriel, N. Brecha, and P. Witkovsky
Somatostatin Modulates Voltage-Gated K+ and Ca2+ Currents in Rod and Cone Photoreceptors of the Salamander Retina
J. Neurosci., February 1, 2000; 20(3): 929 - 936.
[Abstract] [Full Text] [PDF]
D. Krizaj, J.-X. Bao, Y. Schmitz, P. Witkovsky, and D. R. Copenhagen
Caffeine-Sensitive Calcium Stores Regulate Synaptic Transmission from Retinal Rod Photoreceptors
J. Neurosci., September 1, 1999; 19(17): 7249 - 7261.
[Abstract] [Full Text] [PDF]
P. Koulen, R. Kuhn, H. Wassle, and J. H. Brandstatter
Modulation of the intracellular calcium concentration in photoreceptor terminals by a presynaptic metabotropic glutamate receptor
PNAS, August 17, 1999; 96(17): 9909 - 9914.
[Abstract] [Full Text] [PDF]
A. Dmitriev, A. Pignatelli, and M. Piccolino
Resistance of Retinal Extracellular Space to Ca2+ Level Decrease: Implications for the Synaptic Effects of Divalent Cations
J Neurophysiol, July 1, 1999; 82(1): 283 - 289.
[Abstract] [Full Text] [PDF]
J. A. Edwards and H. T. Cline
Light-Induced Calcium Influx Into Retinal Axons Is Regulated by Presynaptic Nicotinic Acetylcholine Receptor Activity In Vivo
J Neurophysiol, February 1, 1999; 81(2): 895 - 907.
[Abstract] [Full Text] [PDF]
|
|
|
|
 |
|