Characterization of Ionic Currents in Human Neural Stem Cells.
10.4196/kjpp.2008.12.4.131
- Author:
Chae Gil LIM
1
;
Sung Soo KIM
;
Haeyoung SUH-KIM
;
Young Don LEE
;
Seung Cheol AHN
Author Information
1. Department of Physiology, College of Medicine, Dankook University, Cheonan, Korea. ansil67@dku.edu
- Publication Type:Original Article
- Keywords:
Human neural stem cells;
TTX-sensitive Na+ current;
A-type;
delayed rectifier;
hyperpolarization-activated inward current
- MeSH:
4-Aminopyridine;
Action Potentials;
Humans;
Membranes;
Neural Stem Cells;
Neurons;
Tetraethylammonium;
Tetrodotoxin
- From:The Korean Journal of Physiology and Pharmacology
2008;12(4):131-135
- CountryRepublic of Korea
- Language:English
-
Abstract:
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+ current, a hyperpolarization-activated inward current, and A-type and delayed rectifier-type K+ outward currents. Both types of K+ 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+ inward current in that it exhibited a voltage-dependent block in the presence of external Ba2+ (30micrometer) or Cs+ (3micrometer). However, the reversal potentials did not match well with the predicted K+ equilibrium potentials, suggesting that it was not a classical K+ inward rectifier current. The other Na+ inward current resembled the classical Na+ 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.
