Structure and Function of Voltage-Dependent Sodium Channels: Comparison of
Brain II and Cardiac Isoforms.
Fozzard, Harry A., and Dorothy A. Hanck.
Departments of the Pharmacological and Physiological Sciences and of
Medicine, and Committees on Cell Physiology and Neurobiology, The University
of Chicago, Chicago, Illinois.
APStracts 2:0010P, 1996.
ABSTRACT
Cardiac and nerve Na channels have broadly similar functional properties and
amino acid sequences, but they demonstrate specific differences in gating,
permeation, ionic block, modulation, and pharmacology. Resolution of three-
dimensional structures of Na channels is unlikely in the near future, but a
number of amino acid sequences from a variety of species and isoforms are
known so that channel differences can be exploited to gain insight into the
relationship of structure to function. The combination of molecular biology to
create chimera and channels with point mutations and high-resolution
electrophysiological techniques to study function encourage the idea that
predictions of structure from function are possible. With the goal of
understanding the special properties of the cardiac Na channel, this review
examines the structural (sequence) similarities between the cardiac and nerve
channel and considers what is known about the relationship of structure to
function for voltage-dependent Na channels in general and for the cardiac Na
channels in particular.
APS Manuscript Number P3-6.
Article publication pending July 1996, Physiological Reviews.
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 4 July 96