Properties of ion channels in rabbit mesenchymal stem cells from bone marrow.
The present study was designed to investigate properties of ion channels in undifferentiated rabbit mesenchymal stem cells (MSCs) from bone marrow using whole-cell patch-clamp and RT-PCR techniques. It was found that three types of outward currents were present in rabbit MSCs, including an inward rectifier K(+) current (I(Kir)), a noise-like Ca(2+)-activated K(+) current (I(KCa)) co-present with delayed rectifier K(+) current (IK(DR)). I(Kir) was inhibited by Ba(2+), while I(KCa) was inhibited by paxilline (a blocker of big conductance I(KCa) channels) and clotrimazole (an inhibitor of intermediate conductance I(KCa) channels). IK(DR) exhibited a slow inactivation, "U-shaped" voltage-dependent inactivation, and slow recovery from inactivation, and the current was inhibited by tetraethylammonium or 4-aminopyridine. RT-PCR revealed the molecular identities for the functional ionic currents, including Kir1.1 (possibly responsible for I(Kir)), KCa1.1 and KCa3.1 (possibly responsible for I(KCa)), and Kv1.2, Kv2.1, and Kv2.2 (possibly responsible for IK(DR)). These results demonstrate for the first time that three types of functional ion channel currents (i.e., I(Kir), I(KCa), and IK(DR)) are present in rabbit MSCs from bone marrow.
Deng
Xiu-Ling
XL
Department of Medicine and Research Centre of Heart, Brain, Hormone and Healthy Aging, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China.
Sun
Hai-Ying
HY
Lau
Chu-Pak
CP
Li
Gui-Rong
GR
D000818:Animals; D001854:Bone Marrow Cells / Q000502:physiology; D002478:Cells, Cultured; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000502:physiology*; D018408:Patch-Clamp Techniques; D015221:Potassium Channels / Q000032:analysis / Q000502:physiology; D011817:Rabbits; D051381:Rats; D013045:Species Specificity
D015221:Potassium Channels