Characterization of Ionic Currents in Human Neural Stem Cells
Characterization of Ionic Currents in Human Neural Stem Cells
- 대한생리학회-대한약리학회
- The Korean Journal of Physiology & Pharmacology
- 제12권 제4호
- : SCOPUS, SCIE, KCI등재
- 2008.01
- 131 - 136 (6 pages)
The profile of membrane currents was investigated in differentiated neuronal cells derived from human neural stem cells (hNSCs) that were obtained from aborted fetal cortex. Whole-cell voltage clamp recording revealed at least 4 different currents: a tetrodotoxin (TTX)-sensitive Na<sup>+</sup> current, a hyperpolarization-activated inward current, and A-type and delayed rectifier-type K<sup>+</sup> outward currents. Both types of K<sup>+</sup> outward currents were blocked by either 5 mM tetraethylammonium (TEA) or 5 mM 4-aminopyridine (4-AP). The hyperpolarization-activated current resembled the classical K<sup>+</sup> inward current in that it exhibited a voltage-dependent block in the presence of external Ba<sup>2+</sup> (30ՌM) or Cs<sup>+</sup> (3ՌM). However, the reversal potentials did not match well with the predicted K<sup>+</sup> equilibrium potentials, suggesting that it was not a classical K<sup>+</sup> inward rectifier current. The other Na<sup>+</sup> inward current resembled the classical Na<sup>+</sup> current observed in pharmacological studies. The expression of these channels may contribute to generation and repolarization of action potential and might be regarded as functional markers for hNSCs-derived neurons.