Expression of the electrophysiological system during murine embryonic stem cell cardiac differentiation.
BACKGROUND
Stem cell based replacement therapy is envisioned as a method to repair failing hearts suffering from cardiomyocyte loss. To prevent potentially lethal arrhythmias, the donor cellular electrophysiological make-up should match with the acceptor tissue. To engineer the desired electrophysiological phenotype, the underlying molecular regulation of ion channels and gap-junction proteins should be clarified first.


METHODS
We established the expression of seven main cardiac ion channel a-subunits and four b-subunits using semiquantitive RT-PCR and two major cardiac gap-junction proteins by immunohistochemistry during the differentiation process of murine ES cells into cardiomyocytes.


RESULTS
Ion channel mRNA expression profiles display sequential upregulation. Connexin-40 and -43 expression is low in early cardiomyocytes, increased expression rates were found in subsequent differentiation phases.


CONCLUSIONS
Cardiac differentiation of mouse embryonic stem cells is characterized by a sequential upregulation of the main cardiac ion channels and connexins.
Department of Medical Physiology, University Medical Center Utrecht, The Netherlands.
Marjan
M
van Kempen
Antoni
A
van Ginneken
Ingrid
I
de Grijs
Nancy
N
Mutsaers
Tobias
T
Opthof
Habo
H
Jongsma
Marcel
M
van der Heyden
D000200:Action Potentials; D000818:Animals; D001483:Base Sequence; D002454:Cell Differentiation; D018031:Connexin 43 / Q000378:metabolism; D004622:Embryo, Mammalian / Q000166:cytology*; D007473:Ion Channels / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D009206:Myocardium / Q000378:metabolism; D032383:Myocytes, Cardiac / Q000166:cytology / Q000502:physiology*; D013234:Stem Cells / Q000166:cytology*; D013997:Time Factors
D018031:Connexin 43; D007473:Ion Channels