From: Science Letter

Three type of ionic currents were identified in mesenchymal stem cells from the bone marrow.

According to a study from People's Republic of China, "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 Call-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 (IKDR)-like ether-a-go-go (eag) K+ channel."

"In addition," said G.R. Li and colleagues at the University of Hong Kong, "tetrodotoxin sensitive sodium current (I-Na.TTx) and nifedipine-sensitive L-type Ca2+ current (I-Ca.L) were also detected in 29 and 15% hMSCs, respectively."

"Moreover," the authors reported, "RTPCR 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-10, heag1 for IKDR, hNE-Na for I-Na.TTX, and CACNAIC for I-Ca.L."

Li concluded, "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 and colleagues published the results of their research in Stem Cells (Characterization of ionic currents in human mesenchymal stem cells from bone marrow. Stem Cells, 2005;23(3):371-382).

For additional information, contact G.R. Li, University Hong Kong, Faculty Med, Department Med, Research Center Heart Brain Hormones & Hlth Aging,

21 Sassoon Rd., Faculty Med Bldg, Laboratory Block, L8-01, Pokfulam, Hong Kong, People's Republic of China.

The publisher of the journal Stem Cells can be contacted at: Alphamed Press,

One Prestige Place, Ste. 290, Miamisburg, OH 45342-3758, USA.