TY - JOUR
T1 - KCNQ channels are involved in the regulatory volume decrease response in primary neonatal rat cardiomyocytes.
AU - Calloe, Kirstine
AU - Nielsen, Morten Schak
AU - Grunnet, Morten
AU - Schmitt, Nicole
AU - Jorgensen, Nanna Koschmieder
N1 - Keywords: Actins; Animals; Animals, Newborn; Anthracenes; Arrhythmias, Cardiac; Cell Adhesion; Cell Size; Cells, Cultured; Cytochalasin D; Electric Conductivity; Ion Transport; KCNQ Potassium Channels; Membrane Potentials; Myocardium; Myocytes, Cardiac; Rats; Rats, Wistar; Reperfusion Injury; Stress Fibers
PY - 2007
Y1 - 2007
N2 - Cardiomyocytes may experience significant cell swelling during ischemia and reperfusion. Such changes in cardiomyocyte volume have been shown to affect the electrical properties of the heart, possibly leading to cardiac arrhythmia. In the present study the regulatory volume decrease (RVD) response of neonatal rat cardiomyocytes was studied in intact single cells attached to coverslips, i.e. with an intact cytoskeleton. The potential contribution of KCNQ (Kv7) channels to the RVD response and the possible involvement of the F-actin cytoskeleton were investigated. The rate of RVD was significantly inhibited in the presence of the KCNQ channel blocker XE-991 (10 and 100 microM). Electrophysiological experiments confirmed the presence of an XE-991 sensitive current and Western blotting analysis revealed that KCNQ1 channel protein was present in the neonatal rat cardiomyocytes. Hypoosmotic cell swelling changes the structure of the F-actin cytoskeleton, leading to a more rounded cell shape, less pronounced F-actin stress fibers and patches of actin. In the presence of cytochalasin D (1 microM), a potent inhibitor of actin polymerization, the RVD response was strongly reduced, confirming a possible role for an intact F-actin cytoskeleton in linking cell swelling to activation of ion transport in neonatal rat cardiomyocytes.
Udgivelsesdato: 2007-Jun
AB - Cardiomyocytes may experience significant cell swelling during ischemia and reperfusion. Such changes in cardiomyocyte volume have been shown to affect the electrical properties of the heart, possibly leading to cardiac arrhythmia. In the present study the regulatory volume decrease (RVD) response of neonatal rat cardiomyocytes was studied in intact single cells attached to coverslips, i.e. with an intact cytoskeleton. The potential contribution of KCNQ (Kv7) channels to the RVD response and the possible involvement of the F-actin cytoskeleton were investigated. The rate of RVD was significantly inhibited in the presence of the KCNQ channel blocker XE-991 (10 and 100 microM). Electrophysiological experiments confirmed the presence of an XE-991 sensitive current and Western blotting analysis revealed that KCNQ1 channel protein was present in the neonatal rat cardiomyocytes. Hypoosmotic cell swelling changes the structure of the F-actin cytoskeleton, leading to a more rounded cell shape, less pronounced F-actin stress fibers and patches of actin. In the presence of cytochalasin D (1 microM), a potent inhibitor of actin polymerization, the RVD response was strongly reduced, confirming a possible role for an intact F-actin cytoskeleton in linking cell swelling to activation of ion transport in neonatal rat cardiomyocytes.
Udgivelsesdato: 2007-Jun
U2 - 10.1016/j.bbamcr.2007.02.008
DO - 10.1016/j.bbamcr.2007.02.008
M3 - Journal article
C2 - 17442416
SN - 0304-4165
VL - 1773
SP - 764
EP - 773
JO - B B A - General Subjects
JF - B B A - General Subjects
IS - 6
ER -