Hostname: page-component-78c5997874-xbtfd Total loading time: 0 Render date: 2024-11-11T03:57:29.016Z Has data issue: false hasContentIssue false
  • English
  • Français

A slowly inactivating K+ current in retinal ganglion cells from postnatal rat

Published online by Cambridge University Press:  02 June 2009

Nikolaus J. Sucher  and
Stuart A. Lipton
Nikolaus J. Sucher
Affiliation:
Laboratory of Cellular and Molecular Neuroscience, Department of Neurology, Children's Hospital, Beth Israel Hospital, Brigham and Women's Hospital, Massachusetts General Hospital, and the Program in Neuroscience, Harvard Medical School, Boston
Stuart A. Lipton
Affiliation:
Laboratory of Cellular and Molecular Neuroscience, Department of Neurology, Children's Hospital, Beth Israel Hospital, Brigham and Women's Hospital, Massachusetts General Hospital, and the Program in Neuroscience, Harvard Medical School, Boston
Get access Rights & Permissions [Opens in a new window]

Abstract

The whole-cell configuration of the patch-clamp technique was used to study voltage-gated K+ conductances in retinal ganglion cells from postnatal rat. Retinal ganglion cells were fluorescently labeled in situ, dissociated from the retina, and maintained in culture. With physiological solutions in the bath and the pipette, depolarizing voltage steps from physiological holding potentials activated Na+-(INa), Ca2+ (ICa), and K+ -currents studied previously in retinal ganglion cells. Here we report on a slowly decaying K+ current, not heretofore reported in rat. With 4-AP, TEA, and Co2+ in the bath, to block IA, IK, and IK(Ca), respectively, a slowly decaying outward current was activated from —80 mV by steps positive to —40 mV. This current was present in 92% of all ganglion cells tested (n = 83). It activated within 10 ms and inactivated with a voltage-independent time constant of about 70 ms at 35°C. Inactivation was voltage-dependent, half-maximal at —55 mV, and almost complete at 0 mV. The current was blocked by internal Cs+ and TEA, or by external application of 1 mM Ba2+, but not by 3 mM extracellular Co2+. The biophysical and pharmacological properties of this current are distinctly different from those of slowly inactivating K+ currents studied in other rat neurons. It was very similar, however, to a slowly inactivating K+ current previously reported in ganglion cells of tiger salamander retina. This last finding indicates conservation of a defined K+ channel type in functionally related cells in both lower vertebrates and mammals.

Keywords

RetinaGanglion cellsPatch clampCell cultureRat
Type
Short Communication
Information
Visual Neuroscience , Volume 8 , Issue 2 , February 1992 , pp. 171 - 176
Copyright
Copyright © Cambridge University Press 1992

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Aizenman, E., Frosch, M. & Lipton, S.A. (1988). Responses mediated by excitatory amino acid receptors in solitary retinal ganglion cells from rat. Journal of Physiology 396, 75–91.Google Scholar
Barres, B.A., Silverstein, B.E., Corey, D.P. & Chun, L.Y. (1988). Immunological, morphological, and electrophysiological variation among retinal ganglion cells purified by panning. Neuron 2, 791–803.Google Scholar
Belluzzi, O., Sacchi, O. & Wanke, E. (1985 a). A fast transient outward current in the rat sympathetic neurone studied under voltage clamp conditions. Journal of Physiology 358, 91–108.CrossRefGoogle ScholarPubMed
Belluzzi, O., Sacchi, O. & Wanke, E. (1985 b). Identification of delayed potassium and calcium currents in the rat sympathetic neurone under voltage clamp. Journal of Physiology 358, 109–129.CrossRefGoogle ScholarPubMed
Bossu, J.-L.Dupont, J.-L. & Feltz, A. (1988). Potassium currents in rat cerebellar Purkinje neurones maintained in culture in L15 (Leibovitz) medium. Neuroscience Letters 89, 55–62.Google Scholar
Butler, A., Wei, A., Baker, K. & Salkoff, L. (1989). A family of putative potassium channel genes in drosophila. Science 243, 943–947.CrossRefGoogle ScholarPubMed
Caldwell, P.C. (1970). Calcium chelation and buffers. In A Symposium on Calcium and Cellular Function, ed. Cuthbert, A.W., pp. 10–16. New York, USA: St. Martin's Press.Google Scholar
Cooper, E. & Shrier, A. (1989). Inactivation of A currents and A channels on rat nodose neurons in culture. Journal of General Physiology 94, 881–910.Google Scholar
Fenwick, E.M., Marty, A. & Neher, E. (1982). A patch clamp study of bovine chromaffin cells and their sensitivity to acetylcholine. Journal of Physiology 331, 577–597.Google Scholar
Hamill, O.P., Marty, A., Nether, E., Sakmann, B. & Sigworth, F.J. (1981). Improved patch-clamp techniques for highresolution current recording from cells and cell-free membrane patches. Pflüugers Archiv 391, 85–100.CrossRefGoogle ScholarPubMed
Isacoff, E.Y., Jan, Y.N. & Jan, L.Y. (1990). Evidence for the formation of heteromultimeric potassium channels in Xenopus oocytes. Nature 345, 530–534.CrossRefGoogle ScholarPubMed
Karschin, A. & Lipton, S.A. (1989). Two components of calcium current in solitary retinal ganglion cells from postnatal rat. Journal of Physiology 418, 379–396.CrossRefGoogle Scholar
Lipton, S.A. (1986). Blockade of electrical activity promotes the death of mammalian retinal ganglion cells in culture. Proceedings of the National Academy of Sciences of the U.S.A. 83, 9774–9778.CrossRefGoogle ScholarPubMed
Lipton, S.A. (1989). GABA-activated single-channel currents in outside-out membrane patches from rat retinal ganglion cells. Visual Neuroscience 3, 275–279.Google Scholar
Lipton, S.A., Aizenman, E. & Loring, R.H. (1987). Neural nicotinic acetylcholine responses in solitary mammalian retinal ganglion cells. Pflüugers Archiv 410, 37–43.Google Scholar
Lipton, S.A. & Tauck, D.L. (1987). Voltage-dependent conductances of solitary ganglion cells dissociated from the rat retina. Journal of Physiology 385, 361–391.Google Scholar
Lukasiewicz, P. & Werblin, F. (1988). A slowly inactivating potassium current truncates spike activityin ganglion cells of the tiger salamander retina. Journal of Neuroscience 8, 4470–4481.Google Scholar
Rudy, B. (1988). Diversity and ubiquity of K channels. Neuroscience 25, 729–749.Google Scholar
Ruppersberger, J.P., Schröter, K.H., Sakmann, B., Stocker, M., Sewing, S. & Pongs, O. (1990). Heteromultimeric channels formed by rat brain potassium-channel proteins. Nature 345, 535–537.Google Scholar
Schofield, G.G. & Ideka, S.R. (1989). Potassium currents of acutely isolated adult rat superior cervical ganglion neurons. Brain Research 485, 205–214.CrossRefGoogle ScholarPubMed
Segal, M. & Barker, J.L. (1984). Rat hippocampal neurons in culture: Potassium conductances. Journal of Neurophysiology 51, 1409–1433.CrossRefGoogle ScholarPubMed
Segal, M., Rogawski, M.A. & Barker, J.L. (1984). A transient potassium conductance regulates the excitability of cultured hippocampal and spinal neurons. Journal of Neuroscience 4, 604–609.CrossRefGoogle ScholarPubMed
Storm, J.F. (1988). Temporal integration by a slowly inactivating K+ current in hippocampal neurons. Nature 336, 379–381.Google Scholar
Stühmer, W., Ruppersberger, J.P., Schröter, K.H., Sakmann, B., Stocker, M., Giese, K.P., Perschke, A., Baumann, A. & Pongs, O. (1989). Molecular basis of functional diversity of voltage-gated potassium channels in mammalian brain. EMBO Journal 8, 3235–3244.CrossRefGoogle ScholarPubMed
Sucher, N.J., Cheng, T.P.O. & Lipton, S.A. (1991 a). Cryopreservation of postnatal rat retinal ganglion cells: Persistence of voltageand ligand-gated ionic currents. Neuroscience 43, 135–150.Google Scholar
Sucher, N.J., Deitcher, D.L., Cepko, C.L. & Lipton, S.A. (1991 b). Patch clamp and PCR on a single rat retinal ganglion cell: Neuronal nicotinic acetylcholine receptor (nAChR) subunits. Investigative Ophthalmology and Visual Science 32, 992.Google Scholar
Sucher, N. & Lipton, S.A. (1989). A slowly inactivating K+ current in postnatal rat retinal ganglion cells. Society for Neuroscience Abstracts 15, 924.Google Scholar
Tauck, D.L., Frosch, M.P. & Lipton, S.A. (1988). Characterization of GABA- and glycine-induced currents of solitary rodent retinal ganglion cells in culture. Neuroscience 27, 193–203.Google Scholar