AJP - Cell Physiology, Vol 259, Issue 2 C181-C195, Copyright © 1990 by American Physiological Society
Basolateral K conductance: role in regulation of NaCl absorption and secretion
D. C. Dawson and N. W. Richards
Department of Physiology, University of Michigan Medical School, Ann Arbor 48109.
In this review we explore the possible role of basolateral K conductance
(gK) in the regulation of salt absorption and secretion. This inquiry is
prompted by a growing body of evidence which, taken together, suggests that
basolateral gK is very labile and that alterations in basolateral gK may be
a key feature in both stimulatory and inhibitory regulatory mechanisms. We
first consider the role of basolateral gK in relation to models for salt
absorption and secretion, particularly in relation to the maintenance of
cellular charge balance and the obligatory coupling between the apical and
basolateral membranes that is produced by transcellular current flow. Next,
we review some of the experimental evidence that suggests that changes in
basolateral gK are associated with transport regulation. The cellular
mechanisms that are known to impact on K channel regulation are considered
in a general way, and finally, we consider the use of integrated models for
understanding possible coordinate regulation of apical and basolateral cell
membranes.
