Summary
Measurements were made of the kinetic and steadystate characteristics of the potassium conductance in the giant axon of the crabCarcinus maenas. These measurements were made in the presence of tetrodotoxin, using the feedback amplifier concept introduced by Dodge and Frankenhaeuser (J. Physiol. (London) 143:76–90). The conductance increase during depolarizing voltage-clamp pulses was analyzed assuming that two separate potassium channels exist in these axons. The first potassium channel exhibited activation and fast inactivation gating which could be fitted using them 3 h, Hodgkin-Huxley formalism. The second potassium channel exhibited the standardn 4 Hodgkin-Huxley kinetics. These two postulated channels are blocked by internal application of caesium, tetraethylammonium and sodium ions. External application of 4 amino-pyridine also blocks these channels.
Similar content being viewed by others
References
Arispe, N., Quinta-Ferreira, M.E., Rojas, E. 1980. Two potassium conductance systems in the giant axon of the crabCarcinus maenas.J. Physiol. (London) 305:87P-88P
Bezanilla, F., Armstrong, C.M. 1972. Negative conductance caused by entry of sodium and caesium ions into the potassium channels of squid axons.J. Gen. Physiol. 60:588–608
Binstock, L., Lecar, H. 1969. Ammonium ion currents in the squid giant axon.J. Gen. Physiol. 53:342–361
Connor, J.A. 1975. Neural repetitive firing: A comparative study of membrane properties of crustacean walking leg axons.J. Neurophysiol. 38:922–932
Connor, J.A., Walter, D., McKown, R. 1977. Neural repetitive firing. Modifications of the Hodgkin-Huxley axon suggested by experimental results from crustacean axons.Biophys. J. 18:81–102
Dodge, F.A., Frankenhaeuser, B. 1958. Membrane currents in isolated frog nerve fibre under voltage clamp conditions.J. Physiol. (London) 143:76–90
Ehrenstein, G., Gilbert, D.L. 1966. Slow changes in potassium permeability in squid giant axon.Biophys. J. 6:553–566
Frankenhaeuser, B., Hodgkin, A.L. 1956. The after-effects of impulses in the giant nerve fibres ofLoligo.J. Physiol. (London) 131:341–376
Hodgkin, A.L., Huxley, A.F. 1952a. The dual effect of membrane potential on sodium conductance in the giant axon ofLoligo.J. Physiol. (London) 116:497–506
Hodgkin, A.L., Huxley, A.F. 1952b. A quantitative description of membrane current and its application to conduction and excitation in nerve.J. Physiol. (London) 117:500–544
Hodgkin, A.L., Huxley, A.F., Katz, B. 1952. Measurement of current-voltage relations in the membrane of the giant axon ofLoligo.J. Physiol. (London) 116:424–448
Keynes, R.D., Rojas, E. 1976. The temporal and steady-state relationships between activation of the sodium conductance and movement of the gating particles in the squid giant axon.J. Physiol. (London) 255:157–189
Quinta-Ferreira, M.E. 1981. Ionic channels in the giant axon of the crabCarcinus maenas. Ph.D. Thesis. School of Biological Sciences, University of East Anglia, Norwich
Quinta-Ferreira, M.E., Arispe, N., Rojas, E. 1982. Sodium currents in the giant axon of the crabCarcinus maenas.J. Membrane Biol. 66:159–169
Swenson, R.P., Jr., Armstrong, C.M. 1981. K+ channels close more slowly in the presence of external K+ and Rb+.Nature (London) 291:427–429
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Quinta-Ferreira, M.E., Rojas, E. & Arispe, N. Potassium currents in the giant axon of the crabCarcinus maenas . J. Membrain Biol. 66, 171–181 (1982). https://doi.org/10.1007/BF01868492
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF01868492