JN Journal of Applied Physiology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

J Neurophysiol 87: 351-360, 2002;
0022-3077/02 $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 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 Web of Science (23)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Stella, S. L.
Right arrow Articles by Thoreson, W. B.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Stella, S. L., Jr.
Right arrow Articles by Thoreson, W. B.

The Journal of Neurophysiology Vol. 87 No. 1 January 2002, pp. 351-360
Copyright ©2002 by the American Physiological Society

A2 Adenosine Receptors Inhibit Calcium Influx Through L-Type Calcium Channels in Rod Photoreceptors of the Salamander Retina

Salvatore L. Stella Jr., Eric J. Bryson, and Wallace B. Thoreson

Department of Pharmacology and Department of Ophthalmology, University of Nebraska Medical Center, Omaha, Nebraska 68198-5540

Stella Jr., Salvatore L., Eric J. Bryson, and Wallace B. Thoreson. A2 Adenosine Receptors Inhibit Calcium Influx Through L-Type Calcium Channels in Rod Photoreceptors of the Salamander Retina. J. Neurophysiol. 87: 351-360, 2002. Presynaptic inhibition is a major mechanism for regulating synaptic transmission in the CNS and adenosine inhibits Ca2+ currents (ICa) to reduce transmitter release at several synapses. Rod photoreceptors possess L-type Ca2+ channels that regulate the release of L-glutamate. In the retina, adenosine is released in the dark when L-glutamate release is maximal. We tested whether adenosine inhibits ICa and intracellular Ca2+ increases in rod photoreceptors in retinal slice and isolated cell preparations. Adenosine inhibited both ICa and the [Ca2+]i increase evoked by depolarization in a dose-dependent manner with ~25% inhibition at 50 µM. An A2-selective agonist, (N6-[2-(3,5-dimethoxyphenyl)-2-(2-methylphenyl)-ethyl]adenosine) (DPMA), but not the A1- or A3-selective agonists, (R)-N6-(1-methyl-2-phenylethyl)adenosine and N6-2-(4-aminophenyl)ethyladenosine, also inhibited ICa and depolarization-induced [Ca2+]i increases. An inhibitor of protein kinase A (PKA), Rp-cAMPS, blocked the effects of DPMA on both ICa and the depolarization-evoked [Ca2+]i increase in rods. The results suggest that activation of A2 receptors stimulates PKA to inhibit L-type Ca2+ channels in rods resulting in a decreased Ca2+ influx that should suppress glutamate release.




This article has been cited by other articles:


Home page
 J. Neurophysiol.Home page
E. C. Steele Jr., X. Chen, P. M. Iuvone, and P. R. MacLeish
Imaging of Ca2+ Dynamics Within the Presynaptic Terminals of Salamander Rod Photoreceptors
J Neurophysiol, December 1, 2005; 94(6): 4544 - 4553.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurophysiol.Home page
D. Cia, A. Bordais, C. Varela, V. Forster, J. A. Sahel, A. Rendon, and S. Picaud
Voltage-Gated Channels and Calcium Homeostasis in Mammalian Rod Photoreceptors
J Neurophysiol, March 1, 2005; 93(3): 1468 - 1475.
[Abstract] [Full Text] [PDF]

Home page
 IOVSHome page
A. T. E. Hartwick, M. R. Lalonde, S. Barnes, and W. H. Baldridge
Adenosine A1-Receptor Modulation of Glutamate-Induced Calcium Influx in Rat Retinal Ganglion Cells
Invest. Ophthalmol. Vis. Sci., October 1, 2004; 45(10): 3740 - 3748.
[Abstract] [Full Text] [PDF]

Home page
 IOVSHome page
L. Baumann, A. Gerstner, X. Zong, M. Biel, and C. Wahl-Schott
Functional Characterization of the L-type Ca2+ Channel Cav1.4{alpha}1 from Mouse Retina
Invest. Ophthalmol. Vis. Sci., February 1, 2004; 45(2): 708 - 713.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurophysiol.Home page
W. B. Thoreson, E. J. Bryson, and K. Rabl
Reciprocal Interactions Between Calcium and Chloride in Rod Photoreceptors
J Neurophysiol, September 1, 2003; 90(3): 1747 - 1753.
[Abstract] [Full Text] [PDF]

Home page
 Mol. Pharmacol.Home page
K. Murphy, V. Gerzanich, H. Zhou, S. Ivanova, Y. Dong, G. Hoffman, G. A. West, H. R. Winn, and J. M. Simard
Adenosine-A2a Receptor Down-Regulates Cerebral Smooth Muscle L-Type Ca2+ Channel Activity via Protein Tyrosine Phosphatase, Not cAMP-Dependent Protein Kinase
Mol. Pharmacol., September 1, 2003; 64(3): 640 - 649.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurosci.Home page
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]

Home page
 J. Neurophysiol.Home page
S. L. Stella Jr., E. J. Bryson, L. Cadetti, and W. B. Thoreson
Endogenous Adenosine Reduces Glutamatergic Output From Rods Through Activation of A2-Like Adenosine Receptors
J Neurophysiol, July 1, 2003; 90(1): 165 - 174.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurophysiol.Home page
A. Straiker and J. M. Sullivan
Cannabinoid Receptor Activation Differentially Modulates Ion Channels in Photoreceptors of the Tiger Salamander
J Neurophysiol, May 1, 2003; 89(5): 2647 - 2654.
[Abstract] [Full Text] [PDF]


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