title: [Expression of Kir2.1, SCN5a and SCN1b channel genes in mouse cardiomyocytes with various electric properties: patch clamp combined with single cell RT-PCR study].
abstract: This study is to explore a new method of investigating molecular basis for electrophysiological properties of early fetal cardiomyocytes. Single embryonic cardiomyocytes of mouse early developmental heart (E10.5) were obtained by a collagenase B digestion approach. After recording spontaneous action potential using whole cell patch clamp technique, the single cell was picked by a glass micropipette, followed by a standard RT-PCR to explore the expression levels of several ion channel genes. Three phenotypes of cardiomyocytes were demonstrated with distinct properties: ventricular-like, atrial-like, and pacemaker-like action potentials. Ventricular-like and atrial-like cells were characterized with much negative maximum diastolic potential (MDP) and a higher V(max) (maximum velocity of depolarization) compared to pacemaker-like cells. MDP of ventricular-like cells was the most negative. In parallel, stronger expression of SCN5a, SCN1b and Kir2.1 were observed in ventricular-like and atrial-like cells compared to that of pacemaker-like cells, where Kir2.1 in ventricular-like cells was the most abundant. Cardiomyocytes with distinct electrophysiological properties had distinct gene expression pattern. Single cell RT-PCR combined with patch clamp technique could serve as a precise detector to analyze the molecular basis of the special electrophysiological characteristics of cardiomyocytes.
authors.affiliation: Department of Physiology, Tongji Medical College of Huazhong University of Science and Technology, Wuhan 430030, China.
authors.forename: Hong-Yan
authors.initials: HY
authors.lastname: Luo
authors.forename: Hua-Min
authors.initials: HM
authors.lastname: Liang
authors.forename: Xin-Wu
authors.initials: XW
authors.lastname: Hu
authors.forename: Ming
authors.initials: M
authors.lastname: Tang
mesh_terms: D000818:Animals; D055724:Electrophysiological Phenomena; D005260:Female; D005333:Fetus; D008297:Male; D051379:Mice; D032383:Myocytes, Cardiac / Q000378:metabolism* / Q000502:physiology*; D062554:NAV1.5 Voltage-Gated Sodium Channel / Q000235:genetics / Q000378:metabolism*; D018408:Patch-Clamp Techniques; D024661:Potassium Channels, Inwardly Rectifying / Q000235:genetics / Q000378:metabolism*; D060888:Real-Time Polymerase Chain Reaction; D062547:Voltage-Gated Sodium Channel beta-1 Subunit / Q000235:genetics / Q000378:metabolism*
chemical_list: C489461:Kir2.1 channel; D062554:NAV1.5 Voltage-Gated Sodium Channel; D024661:Potassium Channels, Inwardly Rectifying; C524974:Scn1b protein, mouse; C568321:Scn5a protein, mouse; D062547:Voltage-Gated Sodium Channel beta-1 Subunit