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Similar properties of cGMP-activated channels between cones and rods in the carp retina

Published online by Cambridge University Press:  02 June 2009

Shu-Ichi Watanabe
Affiliation:
Department of Physiology, Keio University of Medicine, Shinjuki-ju, Tokoyo, 160 Japan
Motohiki Murakami
Affiliation:
Department of Physiology, Keio University of Medicine, Shinjuki-ju, Tokoyo, 160 Japan

Abstract

Using patch-clamp techniques, properties of cGMP-activated channel were studied at a single-channel level in order to examine (1) whether any differences are recognized between the cGMP-activated channels of rods and cones in the same animal species, and (2) whether the channel properties of the same photoreceptor class differ in different animal species. Experiments were performed on inside-out membrane patches excised from outer segments of rods and morphological subtypes of cones in the carp retina. Single-channel activities could be recorded when the patches were perfused with low concentrations of cGMP (<10 μM). Throughout five morphological subtypes of cones and rod, single-channel currents showed no significant rectification at membrane hyperpolarization in a low divalent cation solution, and single-channel conductances were almost the same: 13.8 ± 0.2 pS (mean ± s.e.m., n = 23) in cones and 12.7 ± 0.8 pS (n = 3) in rods. These values were significantly smaller than that reported in catfish cones (about 50 pS), and that in rods of the toad and the tiger salamander (about 25 pS). In rods and all subtypes of cones of the carp, open durations of cGMP activated channels were brief. In addition, kinetic parameters of channel openings and closings showed no differences throughout all subtypes of cones and rod.

Type
Research Articles
Copyright
Copyright © Cambridge University Press 1991

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References

Cobbs, W.H., Barkdoll, A.E., III & Pugh, E.N. Jr (1985). Cyclic GMP increases photocurrent and light sensitivity of retinal cones. Nature 317, 6466.CrossRefGoogle ScholarPubMed
Colquhoun, D., & Sigworth, F.J.. (1983). Fitting and statistical analysis of single-channel records. In Single Channel Recording, ed. Sakmann, B., & Nester, E., pp. 191263. New York: Plenum Press.CrossRefGoogle Scholar
Hárosi, F.I.. (1985). U<raviolet- and violet-absorbing vertebrate visual pigments: dichroic and bleaching properties. In The Visual System, ed. Fein, A., & Levine, J.S., pp. 4155. New York: Alan R. Liss, Inc.Google Scholar
Hárosi, F.I., & Hashimoto, Y.. (1983). U<raviolet visual pigment in a vertebrate: a tetrachromatic cone system in the dace. Science 222, 10211023.CrossRefGoogle Scholar
Haynes, L.W., Kay, A.R., & Yau, K.-W.. (1986). Single cGMP-activated channel activity in excised patches of rod outer segment membrane. Nature 321, 6670.CrossRefGoogle ScholarPubMed
Haynes, L.W., & Yau, K.-W.. (1987). Single cGMP-activated channel activity recorded from excised cone membrane patches. Biophysical Journal 51, 18.Google Scholar
Haynes, L.W., & Yau, K.-W.. (1990). Single-channel measurement from the cGMP-activated conductance of catfish retinal cones. Journal of Physiology 429, 451481.CrossRefGoogle Scholar
Kaneko, A., & Tachibana, M.. (1985). Electrophysiological measurements of the spectral sensitivity of three types of cones in the carp retina. Japanese Journal of Physiology 35, 355365.Google ScholarPubMed
Marc, R.E., & Sperling, H.G.. (1976). Color receptor identities of goldfish cones. Science 191, 487489.CrossRefGoogle Scholar
Matthews, G.. (1987). Single-channel recordings demonstrate that cGMP opens the light-sensitive ion channel of the rod photoreceptor. Proceedings of the National Academy of Sciences of the U.S.A. 84, 299302.CrossRefGoogle ScholarPubMed
Matthews, G., & Watanabe, S.-I.. (1987). Properties of ion channels closed by light and opened by guanosine 3′,5′-cyclic monophosphate in toad retinal rods. Journal of Physiology 389, 691715.CrossRefGoogle Scholar
Matthews, G., & Watanabe, S.-I.. (1988). Activation of single ion channels from toad retinal rod inner segments by cyclic GMP: concentration dependence. Journal of Physiology 403, 389405.CrossRefGoogle ScholarPubMed
Nakatani, K., & Yau, K.-W.. (1986). Light-suppressible, cGMP-activated current recorded from a truncated, internally dialyzed cone preparation. Investigative Ophthalmology and Visual Science (Suppl.) 27, 300.Google Scholar
Nakatani, K., & Yau, K.-W.. (1989). Sodium-dependent calcium extrusion and sensitivity regulation in retinal cones of the salamander. Journal of Physiology 409, 525548.CrossRefGoogle ScholarPubMed
Stell, W.K., & Hárosi, F.I.. (1976). Cone structure and visual pigment content in the retina of the goldfish. Vision Research, 16, 647657.CrossRefGoogle ScholarPubMed
Tomita, T., Kaneko, A., Murakami, M., & Pautler, E.L.. (1967). Spectral response curves of single cones in the carp. Vision Research, 7, 519531.CrossRefGoogle ScholarPubMed
Watanabe, S.-I., & Murakami, M.. (in preparation) Light response of excised patches from cone outer segments of the carp retina.Google Scholar
Yau, K.-W., & Baylor, D.A.. (1989). Cyclic GMP-activated conductance of retinal photoreceptor cells. Annual Review of Neuroscience 12, 289327.CrossRefGoogle ScholarPubMed
Zimmerman, A.L., & Baylor, D.A.. (1986). Cyclic GMP-sensitive conductance of retinal rods consists of aqueous pores. Nature 321, 7072.CrossRefGoogle ScholarPubMed