Selective blockage of K v 1.3 and K v 3.1 channels increases neural progenitor cell proliferation

The modulation of cell proliferation in neural progenitor cells (NPCs) is believed to play a role in neuronal regeneration. Recent studies showed that K + channel activity influenced cell proliferation. Therefore, we examined NPCs for K + channels and tested whether NPC self renewing can be modulated by synthetic K + channel modulators. The whole‐cell K + current was partly K + dependent and showed a cumulative inactivating component. Two tetra‐ethyl‐ammonium ion (TEA)‐sensitve K + currents with different voltage dependencies ( = 65 μ m , E 50  = −0.3 ± 1.3 mV and  = 8 m m , E 50  = −15.2 ± 2.8 mV) and an almost TEA‐insensitive current were identified. Kaliotoxin blocked approximately 50% of the entire K + currents (IC 50  = 0.25 n m ). These properties resembled functional characteristics of K v 1.4, K v 1.3 and K v 3.1 channels. Transcripts for these channels, as well as proteins for K v 1.3 and K v 3.1, were identified. Immunocytochemical staining revealed K v 1.3 and K v 3.1 K + channel expression in almost all NPCs. The blockage of K v 3.1 by low concentrations of TEA, as well as the blockage of K v 1.3 by Psora‐4, increased NPC proliferation. These findings underline the regulatory role of K + channels on the cell cycle and imply that K + channel modulators might be used therapeutically to activate endogenous NPCs.