Summary
The effect of ultraviolet radiation on the asymmetrical displacement currents in the membrane of the node of Ranvier was measured and compared with the ultraviolet blocking of the sodium current. Ultraviolet radiation irreversibly reduced the peak sodium current and the charge displaced during a depolarizing test pulse, the relative reduction being independent of potential. The ratio of the ultraviolet sensitivities of the sodium and the asymmetrical displacement currents is 2.3±0.2. This result suggests two independent identical gating particles per sodium channel in the membrane of myelinated nerve.
Similar content being viewed by others
References
Fox, J. M.: Selective blocking of the nodal sodium channels by ultraviolet radiation: I. Phenomenology of the radiation effect. Pflügers Arch.351, 287–301 (1974)
Fox, J. M.: Selective blocking of the nodal sodium channels by ultraviolet radiation: II. The interaction of Ca2+, H+, and membrane potential. Pflügers Arch.351, 303–314 (1974)
Fox, J. M., Stämpfli, R.: Modification of ionic membrane currents of Ranvier nodes by UV-radiation under voltage clamp conditions. Experientia (Basel)27, 1289–1290 (1971)
Nonner, W., Rojas, E., Stämpfli, R.: Displacement currents in the node of Ranvier. Voltage and time dependence. Pflügers Arch.354, 1–18 (1975)
Oxford, G., Pooler, J.: Ultraviolet photoalteration of ion channels in voltage clamped lobster giant axons. J. Membrane Biol.20, 13–30 (1975)
Author information
Authors and Affiliations
Additional information
Supported by Deutsche Forschungsgemeinschaft SFB 38 “Membranforschung”-Bonn-Bad Godesberg
Rights and permissions
About this article
Cite this article
Fox, J.M., Neumcke, B., Nonner, W. et al. Block of gating currents by ultraviolet radiation in the membrane of myelinated nerve. Pflugers Arch. 364, 143–145 (1976). https://doi.org/10.1007/BF00585182
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00585182