Modulation of smooth muscle phenotype in vitro by homologous cell substrate.
Tao, F., S. Chaudry, B. Tolloczko, J. G. Martin, and S. M. Kelly.
1Meakins-Christie Laboratories, Department of Medicine, McGill University,
Montreal, Quebec, Canada H2X 2P2; and 2Department of Environmental Health,
Harvard School of Public Health, Boston, Massachusetts 02115
APStracts 10:0074C, 2003.
We have developed a novel cell culture system that supports the shortening of smooth
muscle cells. Primary rat airway smooth muscle cells were plated on an ethanol-fixed,
confluent monolayer of homologous smooth muscle cells (homologous cell substrate,
HCS). Cells grown on HCS exhibited morphological and functional characteristics
consistent with a differentiated phenotype. Cells on HCS were spindle shaped with a
well-defined long axis, whereas cells grown on glass were larger and irregularly shaped.
Smooth muscle-specific a-actin immunostained diffusely in cells on HCS, whereas it
appeared as stress fibers in cells on glass. Agonists recruited a greater fraction of HCS
cells to contract, resulting in greater changes in cell area or length on average, but the
maximal capacity of shortening of individual cells was similar between the groups.
Unlike cells on glass, cells on HCS shortened to methacholine. Cell shortening on HCS
was reversible and persisted over several passages. Agonists stimulated intracellular
Ca2+ oscillations in cells on HCS, whereas they elicited biphasic peak and plateau
transients in cells on glass. HCS modulates smooth muscle cell phenotype in vitro.
Received 7 June 2002; accepted in final form 10 February 2003
APS Manuscript Number C264-2.
Article publication pending Am J Physiol Cell Physiol
ISSN 1080-4757 Copyright 2003 The American Physiological Society.
Published in APStracts on 25 March 2003