Hostname: page-component-586b7cd67f-dsjbd Total loading time: 0 Render date: 2024-11-25T11:57:00.844Z Has data issue: false hasContentIssue false

The determination of total cGMP levels in rod outer segments from intact toad photoreceptors in response to light superimposed on background and to consecutive flashes: A second light flash accelerates the dark recovery rate of cGMP levels in control media, but not in Na+-free, low Ca2+ medium

Published online by Cambridge University Press:  02 June 2009

Adolph I. Cohen
Affiliation:
Departments of Biochemistry and Molecular Biophysics and Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis
Christine Blazynski
Affiliation:
Departments of Biochemistry and Molecular Biophysics and Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis

Abstract

In previous experiments we established that a light flash reduced cGMP levels of toad rod outer segments within the transduction time interval, but that recovery of the dark level of cGMP occurred more slowly than reported electrophysiological recovery of membrane potential. We now report that a second light flash accelerates the recovery rate of total cGMP following an initial flash, but that this acceleration is blocked in a medium which is both sodium and calcium deficient. We also noted that calcium deficiency only elevated cGMP levels when sodium was present. For other experiments, we recorded ERG or aspartate isolated PIII responses from eyecups or retinas mounted on our quick-freeze apparatus, the light stimuli originating from the double light-bench of the latter. Whereas background illumination depressed cGMP, no detectable further cGMP loss accompanied the electrical response to a flash superimposed on the background.

Type
Research Articles
Copyright
Copyright © Cambridge University Press 1993

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

Arshavsky, V.Yu., Dizhoor, A.M., Shestakova, I.K. & Philippov, P.P. (1985). The effect of rhodopsin phosphorylation on the light-dependent activation of phosphodiesterase from bovine rod outer segments. FEBS Letters 181, 264266.CrossRefGoogle ScholarPubMed
Arshavsky, V.Yu, Gray-Keller, M.P. & Bownds, M.D. (1991). cGMP suppresses GTPase activity of a portion of transducin equimolar to phosphodiesterase in frog rod outer segments. Journal of Biological Chemistry 266, 1853018537.Google Scholar
Bennett, N. & Sitaramayya, A. (1988). Inactivation of photoexcited rhodopsin in retinal rods: The role of rhodopsin kinase and 48-kDa protein (arrestin). Biochemistry 27, 17101715.CrossRefGoogle Scholar
Blazynski, C. & Cohen, A.I. (1986). Rapid decline in cyclic GMP of rod outer segments of intact frog photoreceptors after illumination. Journal of Biological Chemistry 261, 1414214147.CrossRefGoogle ScholarPubMed
Capovilla, M., Caretta, A., Cervetto, L. & Torre, V. (1983). Ionic movements through light-sensitive channels of toad rods. Journal of Physiology 343, 295310.CrossRefGoogle ScholarPubMed
Cohen, A.I. & Blazynski, C. (1988). Light-induced losses and dark recovery rates of guanosine 3′,5′-cyclic monophosphate in rod outer segments of intact amphibian photoreceptors. Journal of General Physiology 92, 731746.CrossRefGoogle ScholarPubMed
Cohen, A.I., Hall, A.I. & Ferrendelli, J.A. (1978). Calcium and cyclic nucleotide regulation in incubated mouse retinas. Journal of General Physiology 71, 595612.CrossRefGoogle ScholarPubMed
Cote, R.H., Biernbaum, M.S., Nicol, G.D. & Bownds, M.D. (1984). Light-induced decreases in cGMP concentration precede changes in membrane permeability in frog rod photoreceptors. Journal of Biological Chemistry 259, 96359641.CrossRefGoogle ScholarPubMed
Dawis, S.M., Graeff, R.M., Heyman, R.A., Walseth, T.F. & Goldberg, N.D. (1988). Regulation of cyclic GMP metabolism in toad photoreceptors. Definition of the metabolic events subserving photoexcited and attenuated states. Journal of Biological Chemistry 263, 87718785.CrossRefGoogle ScholarPubMed
Fain, G.L. (1976). Sensitivity of toad rods: Dependence on wavelength and background illumination. Journal of Physiology 261, 71101.CrossRefGoogle ScholarPubMed
Fain, G.L., Lamb, T.D., Matthews, H.R. & Murphy, R.L.W. (1989). Cytoplasmic calcium as the messenger for light adaptation in salamander rods. Journal of Physiology 416, 215243.CrossRefGoogle ScholarPubMed
Fleischmann, D. & Denisevich, M. (1979). Guanylate cyclase of isolated bovine rod axonemes. Biochemistry 18, 50605066.CrossRefGoogle Scholar
Forti, S., Menini, A., Rispoli, G. & Torre, V. (1989). Kinetics of phototransduction in retinal rods of the newt Triturus cristatus. Journal of Physiology 419, 265295.CrossRefGoogle ScholarPubMed
Harper, J.F. & Brooker, G. (1975). Femtomole sensitive radioimmunoassay for cyclic AMP and cyclic GMP after 2′0 acetylation by acetic anhydride in aqueous solution. Journal of Cyclic Nucleotide Research 1, 207218.Google ScholarPubMed
Hodgkin, A.L., McNaughton, P.A. & Nunn, B.J. (1987). Measurement of sodium-calcium exchange in salamander rods. Journal of Physiology 391, 347370.CrossRefGoogle ScholarPubMed
Jones, G.J. (1984). On estimating freezing times during rapid tissue freezing. Journal of Microscopy 136, 349360.CrossRefGoogle Scholar
Koch, K.-W. & Stryer, L. (1988). Highly cooperative feedback control of retinal rod guanylate cyclase by calcium ions. Nature 334, 6466.CrossRefGoogle ScholarPubMed
Lolley, R.N. & Racz, E. (1982). Calcium modulation of cyclic GMP synthesis in rat visual cells. Vision Research 22, 14811486.CrossRefGoogle ScholarPubMed
Lowry, O.H., Rosebrough, N.J., Farr, A.L. & Randall, R.J. (1951). Protein measurement with the Folin phenol reagent. Journal of Biological Chemistry 193, 265275.CrossRefGoogle ScholarPubMed
Matthews, H.R., Murphy, R.L.W., Fain, G.L. & Lamb, T.D. (1988). Photoreceptor light adaptation is mediated by cytoplasmic calcium concentration. Nature 334, 6769.CrossRefGoogle ScholarPubMed
Nicol, G.D. & Bownds, M.D. (1989). Calcium regulates some, but not all aspects of light adaptation in rod photoreceptors. Journal of General Physiology 94, 233259.CrossRefGoogle Scholar
Pepe, I.M., Panfoli, I. & Hamm, H.E. (1986). Effect of light and calcium on cyclic GMP synthesis in rod outer segments of toad retina. FEBS Letters 203, 7376.CrossRefGoogle ScholarPubMed
Pugh, E.N. & Lamb, T.D. (1990). Cyclic GMP and calcium: The internal messengers of excitation and adaptation in vertebrate photoreceptors. Vision Research 30, 19231948.CrossRefGoogle ScholarPubMed
Sitaramayya, A. (1986). Rhodopsin kinase prepared from bovine rod disk membrane quenches light activation of cGMP phosphodiesterase in a reconstituted system. Biochemistry 25, 54605468.CrossRefGoogle Scholar
Sitaramayya, A., Virmaux, N. & Mandel, P. (1977). On a soluble system for studying light activation of rod outer segment cyclic GMP phosphodiesterase. Neurochemical Research 2, 110.CrossRefGoogle ScholarPubMed
Steiner, A.L., Parker, C.W. & Kipnes, D.M. (1972). Radioimmuno-assay for cyclic nucleotides. Journal of Biological Chemistry 247, 11061113.CrossRefGoogle Scholar
Stryer, L. (1991). Visual Excitation and Recovery. Journal of Biological Chemistry 266, 1071110714.CrossRefGoogle ScholarPubMed
Vuong, T.M. & Chabre, M. (1990). Subsecond deactivation of transduction by endogenous GTP hydrolysis. Nature 346, 7174.CrossRefGoogle ScholarPubMed
Whalen, M.M., Bitensky, M.W. & Takemoto, D.J. (1990). The effect of the 7-subunit of the cGMPphosphodiesterase of bovine and frog (Rana catesbiana) retinal rod outer segments on the kinetic parameters of the enzyme. Biochemical Journal 265, 655658.CrossRefGoogle Scholar
Wilden, U., Hall, S.W. & Kuhn, H. (1986). Phosphodiesterase activation by photoexcited rhodopsin is quenched when rhodopsin is phosphorylated and binds the intrinsic 48-kDa protein of rod outer segments. Proceedings of the National Academy of Sciences of the U.S.A. 83, 11741178.CrossRefGoogle ScholarPubMed
Yau, K.-W. & Nakatani, K. (1985). Light suppressible cyclic GMP conductance in the plasma membrane of a truncated rod outer segment. Nature 317, 252255.CrossRefGoogle ScholarPubMed
Yau, K.-W. & Nakatani, K. (1984 a). Cation selectivity of light sensitive conductance in retinal rods. Nature 309, 352354.CrossRefGoogle ScholarPubMed
Yau, K.-Y. & Nakatani, K. (1984 b). Electrogenic Na-Ca exchange in retinal rod outer segment. Nature 311, 661663.CrossRefGoogle ScholarPubMed
Yau, K.-Y., Haynes, L.W. & Nakatani, K. (1986). Roles of calcium and cyclic GMP in visual transduction. Fortschritte der Zoologie 33, 343366.Google Scholar