Abstract
The coupling between steady-state activation and availability from inactivation was characterized for the cardiac Na+ channel. To evaluate this coupling, we plotted the relationship between the conductance and availability curve midpoint potentials measured in 92 rat ventricular cardiomyocytes and applied a correlation analysis. We found a high correlation between the midpoints (correlation coefficient = 0.86, slope = 0.95) within the availability midpoint potential range positive to -100 mV. In contrast, the midpoints were not correlated in the myocytes (37 of 92 cells) having mid point potential negative to -100 mV, indicating an uncoupling between activation and availability.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
Author information
Authors and Affiliations
Additional information
Received 1 October 1997; received after revision 28 October 1997; accepted 13 November 1997
Rights and permissions
About this article
Cite this article
Maltsev, V., Undrovinas, A. Relationship between steady-state activation and availability of cardiac sodium channel: evidence of uncoupling. CMLS, Cell. Mol. Life Sci. 54, 148–151 (1998). https://doi.org/10.1007/s000180050135
Published:
Issue Date:
DOI: https://doi.org/10.1007/s000180050135