AJP - Cell Physiology, Vol 255, Issue 1 C102-C111, Copyright © 1988 by American Physiological Society
Different physiological signatures of sweat gland secretory and duct cells in culture
C. J. Jones, C. L. Bell and P. M. Quinton
Division of Biomedical Sciences, University of California, Riverside 92521-0121.
Human eccrine sweat gland cells grown in culture were found to lose their
characteristic shape, becoming flattened and organized into multilayers.
The resting membrane potentials of the cultured secretory cells (-35 +/- 2
mV, n = 36) were significantly higher than those measured for cultured duct
cells (-22 +/- 1 mV, n = 58, P less than or equal to 0.01). When the
cholinergic agonist methacholine (10(-5) or 10(-6) M) was administered, the
cultured secretory cells could be distinguished unequivocally by their
atropine-sensitive hyperpolarizing response (-20 +/- 2 mV, n = 43), whereas
no cultured duct cells responded. When the sodium conductance antagonist
amiloride (10(-5) or 10(-6) M) was administered, 44% of cultured secretory
cells responded by hyperpolarization (-8 +/- 1 mV, n = 8), whereas 87% of
cultured duct cells hyperpolarized (-15 +/- 1 mV, n = 46) and by a
significantly greater margin (P less than or equal to 0.01). Substitution
of chloride with gluconate in the bathing medium caused membrane potential
depolarization in both cultured secretory and duct cell populations, which
is consistent with the presence of a chloride conductance in the plasma
membrane. The beta-adrenoceptor agonist isoproterenol induced a transient
hyperpolarization of 5-10 mV in three out of six cultured secretory cells
tested but had no effect on cultured duct cells.
