Characterization of ionic currents in human mesenchymal stem cells from bone marrow.
This study characterized functional ion channels in cultured undifferentiated human mesenchymal stem cells (hMSCs) from bone marrow with whole-cell patch clamp and reverse transcription polymerase chain reaction (RT-PCR) techniques. Three types of outward currents were found in hMSCs, including a noise-like rapidly activating outward current inhibited by the large conductance Ca(2+)-activated K(+) channel (I(KCa)) blocker iberiotoxin, a transient outward K(+) current (I(to)) suppressed by 4-aminopyridine (4-AP), and a delayed rectifier K(+) current (IK(DR))-like ether-à-go-go (eag) K(+) channel. In addition, tetrodotoxin-sensitive sodium current (I(Na.TTX)) and nifedipine-sensitive L-type Ca(2+) current (I(Ca.L)) were also detected in 29% and 15% hMSCs, respectively. Moreover, RT-PCR revealed the molecular evidence of high levels of mRNA for the functional ionic currents, including human MaxiK for I(KCa), Kv4.2 and Kv1.4 for I(to), heag1 for IK(DR), hNE-Na for I(Na.TTX), and CACNAIC for I(Ca.L). These results demonstrate that multiple functional ion channel currents--that is, I(KCa), I(to), heag1, I(Na.TTX), and I(Ca.L)--are expressed in hMSCs from bone marrow.
Li
Gui-Rong
GR
Department of Medicine, Research Centre on Heart, Brain, Hormones and Healthy Aging, The University of Hong Kong, Pokfulam, Hong Kong SAR, China. grli@hkucc.hku.hk
Sun
Haiying
H
Deng
Xiuling
X
Lau
Chu-Pak
CP
D015761:4-Aminopyridine / Q000494:pharmacology; D001854:Bone Marrow Cells / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D020746:Calcium Channels, L-Type / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D002454:Cell Differentiation; D002478:Cells, Cultured; D051638:Ether-A-Go-Go Potassium Channels; D015870:Gene Expression / Q000235:genetics; D006801:Humans; D007473:Ion Channels / Q000235:genetics / Q000502:physiology*; D051665:Kv1.4 Potassium Channel; D051037:Large-Conductance Calcium-Activated Potassium Channel alpha Subunits; D051036:Large-Conductance Calcium-Activated Potassium Channels; D008564:Membrane Potentials / Q000187:drug effects; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D062556:NAV1.7 Voltage-Gated Sodium Channel; D009419:Nerve Tissue Proteins / Q000235:genetics; D009543:Nifedipine / Q000494:pharmacology; D018408:Patch-Clamp Techniques; D010455:Peptides / Q000494:pharmacology; D015221:Potassium Channels / Q000235:genetics; D024681:Potassium Channels, Calcium-Activated / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D024642:Potassium Channels, Voltage-Gated / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051672:Shal Potassium Channels; D015222:Sodium Channels / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D013779:Tetrodotoxin / Q000494:pharmacology
C079146:CACNA1C protein, human; D020746:Calcium Channels, L-Type; D051638:Ether-A-Go-Go Potassium Channels; D007473:Ion Channels; C496977:KCNA4 protein, human; C497018:KCND2 protein, human; C494841:KCNMA1 protein, human; D051665:Kv1.4 Potassium Channel; D051037:Large-Conductance Calcium-Activated Potassium Channel alpha Subunits; D051036:Large-Conductance Calcium-Activated Potassium Channels; D062556:NAV1.7 Voltage-Gated Sodium Channel; D009419:Nerve Tissue Proteins; D010455:Peptides; D015221:Potassium Channels; D024681:Potassium Channels, Calcium-Activated; D024642:Potassium Channels, Voltage-Gated; D012333:RNA, Messenger; C486866:SCN9A protein, human; D051672:Shal Potassium Channels; D015222:Sodium Channels; D013779:Tetrodotoxin; C064719:iberiotoxin; D015761:4-Aminopyridine; D009543:Nifedipine