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ISSN 2522-9028 (Print)
ISSN 2522-9036 (Online)

Fiziologichnyi Zhurnal

is a scientific journal issued by the

Bogomoletz Institute of Physiology
National Academy of Sciences of Ukraine

Editor-in-chief: V.F. Sagach

The journal was founded in 1955 as
1955 – 1977 "Fiziolohichnyi zhurnal" (ISSN 0015 – 3311)
1978 – 1993 "Fiziologicheskii zhurnal" (ISSN 0201 – 8489)
1994 – 2016 "Fiziolohichnyi zhurnal" (ISSN 0201 – 8489)
2017 – "Fiziolohichnyi zhurnal" (ISSN 2522-9028)

Fiziol. Zh. 2012; 58(3): 50-59

Dynamical electrical states of heterogeneous populations of ion channels in the membranes of excitable cells

Korogod SM, Kulagina IB.

    International Center for Molecular Physiology(Dnipropetrovsk Division), National Academy of Sciencesof Ukraine.


In computer models, we studied instantaneous (time-varying) current-voltage relationships (iIVs) of populations of ion channels characteristic of the membrane of different type excitable cells, of which the responses to electrical stimuli essentially differ: giant squid axon (Hodgkin-Huxley model), cardiomyocyte, dendrites of CA3 hippocampal pyramidal neurons and Purkinje neurons of the cerebellum. The membrane potential was stepped from the rest level to a certain depolarization test level that was clamped for a certain time, and the total current was measured at different moments after the step onset. For each iIV zero-current points (potentials) were determined. A set of such points, which were situated on the limb of iIV positive slop and corresponded to the state of high membrane depolarization (excitation state, upstate) at different time moments, were used to characterize the dynamics of the excitation state in time. With these indicators the axon membrane was characterized by a single excitation state that rapidly occurred (0.25 ms) and was short-lasting (decayed from -45 to 40 mV during life-time of 5.5 ms). There were two such states of the membrane of cardiomyocyte. The frst one was early, rapidly occurring and short-living (rapidly relaxing). It occurred shortly after the depolarization start and lasted for 14.5 ms. The second one was late, slowly rising and long-lasting (occurred with a 7.5-ms delay, increased from 11 to 46 mV in 39 ms and then relaxed lasting for 623 ms in total). The dendritic membrane of СА3 neurons had one long-lasting excitation state that occurred shortly after the depolarization shift, frst rapidly relaxed during 3 ms from initial 30 mV level to -10 mV and then slowly, in 80 ms, stabilized at the level of -20 mV. In the Purkinje neuron membrane two short-lasting and one very long-lasting excitation states were revealed. The frst state of very high (>100 mV) depolarization relaxed to 4 mV in 0.8 ms. Shortly before its vanishing, at 0.7 ms, the second short-lasting state emerged, which relaxed in 1 ms from -22 mV tо -48 mV. At 1.8 ms a new excitation state emerged, which after a transient relaxation stabilized at -29.65 mV starting from 88 ms. Thus, iIVs allowed disclosing a fne organization of the states of electrical excitation of the membrane and revealing, in populations of ion channels of different content, existence of different number of the mentioned states, which differ from each other in occurrence time and life-time.


  1. Khodorov B.I. General physiology of excitable membranes. M .: Nauka, 1975 . 405 p.
  3. Armstrong C.M. Time course of TEA(+)-induced anomalous rectifcation in squid giant axons . J. Gen. Physiol. 1966. 50, N 2. P. 491-503. CrossRef PubMed PubMedCentral
  5. Beeler G.W., Reuter H. Reconstruction of the action potential of ventricular myocardial fbres . J. Physiol. 1977. 268, N 1. P. 177-210. CrossRef PubMed PubMedCentral
  7. Dodge F. A study of ionic permeability changes underlying excitation in myelinated nerve fbres of the frog. New York: The Rockefeller University, 1963. 120 p.
  9. Furukawa T., Kimura S., Furukawa N., Bassett A.L., Myerburg R.J. Potassium rectifier currents differ in myocytes of endocardial and epicardial origin . Circulat. Res. 1992. 70, N 1. P. 91-103. CrossRef PubMed
  11. Giles W.R., Imaizumi Y. Comparison of potassium currents in rabbit atrial and ventricular cells . J. Physiol. 1988. 405, Nov. P. 123-145. CrossRef PubMed PubMedCentral
  13. Hemond P. , Epstein D., Boley A., Migliore M., Ascoli G.A., Jaffe D.B. Distinct classes of pyramidal cells exhibit mutually exclusive fring patterns in hippocampal area CA3b . Hippocampus. 2008. 18, N 4. P. 411-424. CrossRef PubMed PubMedCentral
  15. Hines M.L., Carnevale N.T. The NEURON simulation environment . Neural Computation. 1997. 9, N 6. P. 1179-1209. CrossRef PubMed
  17. Hines M.L., Morse T., Migliore M., Carnevale N.T., Shepherd G.M. ModelDB: A Database to support computational neuroscience . J. Comp. Neurosci. 2004. 17, N 1. P. 7-11. CrossRef PubMed PubMedCentral
  19. Hodgkin A.L., Huxley A.F. A quantitative description of membrane current and its application to conduction and excitation in nerve . J. Physiol. 1952. 11 7 , N 4. P. 500-544. CrossRef PubMed PubMedCentral
  21. Kiehn O., Eken T. Functional role of plateau potentials in vertebrate motor neurons . Curr. Opin. Neurobiol. 1998. 8, N 6. P. 746-752. CrossRef  
  22. Korogod S.M., Novorodovskaya T.S. Impact of Geometrical Characteristics of the Organellar Store and Organelle-Free Cytosol on Intracellular Calcium Dynamics in the Dendrite: a Simulation Study . Neurophysiology. Neirofziologiya. 2009. 41, N 1. P. 16-27. CrossRef  
  23. Kulagina I.B., Korogod S.M., Horcholle-Bossavit G., Batini C., Tyc-Dumont S. The electro-dynamics of the dendritic space in Purkinje cells of the cerebellum . Arch. Ital. Biol. 2007. 145, N . 3. 4. P. 211-233.
  25. Migliore M., Morse T.M., Davison A.P., Marenco L., Shepherd G.M., Hines M.L. ModelDB: making models publicly accessible to support computational neuroscience . Neuroinformatics. 2003. 1, N 1. P. 135-139. CrossRef PubMed
  27. Miyasho T., Takagi H., Suzuki H., Watanabe S., Inoue M., Kudo Y., Miyakawa H. Low-threshold potassium channels and a low-threshold calcium channel regulate Ca2+ spike fring in the dendrites of cerebellar Purkinje neurons: a modeling study . Brain Res. 2001. 891, N 1-2. P. 106-115. CrossRef  

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