Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1990 Mar;95(3):411-37.
doi: 10.1085/jgp.95.3.411.

Kinetic analysis of single sodium channels from canine cardiac Purkinje cells

B E Scanley  1 , D A Hanck, T Chay, H A Fozzard
Affiliations

Kinetic analysis of single sodium channels from canine cardiac Purkinje cells

B E Scanley et al. J Gen Physiol. 1990 Mar.

Abstract

Single sodium channel events were recorded from cell-attached patches on single canine cardiac Purkinje cells at 10-13 degrees C. Data from four patches containing two to four channels and one patch with one channel were selected for quantitative analysis. The channels showed prominent reopening behavior at voltages near threshold, and the number of reopenings declined steeply with depolarization. Mean channel open time was a biphasic function of voltage with the maximum value (1-1.5 ms) occurring between -50 and -40 mV and lower values at more and at less hyperpolarized levels. Inactivation without opening was also prominent near threshold, and this occurrence also declined with depolarization. The waiting time distributions and the probability of being open showed voltage and time dependence as expected from whole-cell current studies. The results were analyzed in terms of a five-state Markovian kinetic model using both histogram analysis and a maximum likelihood method to estimate kinetic parameters. The kinetic parameters of the model fits were similar to those of GH3 pituitary cells (Horn, R., and C. A. Vandenberg. 1984. Journal of General Physiology. 84:505-534) and N1E115 neuroblastoma cells (Aldrich, R. W., and C. F. Stevens. Journal of Neuroscience. 7:418-431). Both histogram and maximum likelihood analysis implied that much of the voltage dependence of cardiac Na current is in its activation behavior, with inactivation showing modest voltage dependence.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. J Theor Biol. 1988 Jun 22;132(4):449-68 - PubMed
    1. J Gen Physiol. 1984 Oct;84(4):505-34 - PubMed
    1. J Clin Invest. 1989 Jul;84(1):331-6 - PubMed
    1. Annu Rev Biophys Bioeng. 1983;12:319-56 - PubMed
    1. J Neurosci. 1987 Feb;7(2):418-31 - PubMed

Publication types

Substances