Details
| Original language | English |
|---|---|
| Pages (from-to) | 311-322 |
| Number of pages | 12 |
| Journal | Journal of Bioenergetics and Biomembranes |
| Volume | 43 |
| Issue number | 3 |
| Publication status | Published - 27 Dec 2011 |
Abstract
Whole-cell patch-clamp analysis revealed a resting membrane potential of -60 mV in primary osteoblasts and in the MG-63 osteoblast-like cells. Depolarization-induced action potentials were characterized by duration of 60 ms, a minimal peak-to-peak distance of 180 ms, a threshold value of -20 mV and a repolarization between the spikes to -45 mV. Expressed channels were characterized by application of voltage pulses between -150 mV and 90 mV in 10 mV steps, from a holding potential of -40 mV. Voltages below -60 mV induced an inward current. Depolarizing voltages above -30 mV evoked two currents: (a) a fast activated and inactivated inward current at voltages between -30 and 30 mV, and (b) a delayed-activated outward current that was induced by voltages above -30 mV. Electrophysiological and pharmacological parameters indicated that hyperpolarization activated strongly rectifying K + (K ir) channels, whereas depolarization activated tetrodotoxin sensitive voltage gated Na + (Na v) channels as well as delayed, slowly activated, non-inactivating, and tetraethylammonium sensitive voltage gated K + (K v) channels. In addition, RT-PCR showed expression of Na v1.3, Na v1.4, Na v1.5, Na v1.6, Na v1.7, and K ir2.1, K ir2.3, and K ir2.4 as well as K v2.1. We conclude that osteoblasts express channels that allow firing of action potentials.
Keywords
- Action potential, K, MG-63 cells, Na, Osteoblasts, RT-PCR
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)
- Physiology
- Biochemistry, Genetics and Molecular Biology(all)
- Cell Biology
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In: Journal of Bioenergetics and Biomembranes, Vol. 43, No. 3, 27.12.2011, p. 311-322.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Action potentials in primary osteoblasts and in the MG-63 osteoblast-like cell line
AU - Pangalos, Maria
AU - Bintig, Willem
AU - Schlingmann, Barbara
AU - Feyerabend, Frank
AU - Witte, Frank
AU - Begandt, Daniela
AU - Heisterkamp, Alexander
AU - Ngezahayo, Anaclet
N1 - Funding information: Acknowledgments The authors thank Prof. Dr. Helge Küster and his team for discussion on the manuscript. The work was supported by the BMBF project NANOTOME (Biophotonik III), the DFG project (Transregio 37) and by Boehringer Ingelheim International GmbH.
PY - 2011/12/27
Y1 - 2011/12/27
N2 - Whole-cell patch-clamp analysis revealed a resting membrane potential of -60 mV in primary osteoblasts and in the MG-63 osteoblast-like cells. Depolarization-induced action potentials were characterized by duration of 60 ms, a minimal peak-to-peak distance of 180 ms, a threshold value of -20 mV and a repolarization between the spikes to -45 mV. Expressed channels were characterized by application of voltage pulses between -150 mV and 90 mV in 10 mV steps, from a holding potential of -40 mV. Voltages below -60 mV induced an inward current. Depolarizing voltages above -30 mV evoked two currents: (a) a fast activated and inactivated inward current at voltages between -30 and 30 mV, and (b) a delayed-activated outward current that was induced by voltages above -30 mV. Electrophysiological and pharmacological parameters indicated that hyperpolarization activated strongly rectifying K + (K ir) channels, whereas depolarization activated tetrodotoxin sensitive voltage gated Na + (Na v) channels as well as delayed, slowly activated, non-inactivating, and tetraethylammonium sensitive voltage gated K + (K v) channels. In addition, RT-PCR showed expression of Na v1.3, Na v1.4, Na v1.5, Na v1.6, Na v1.7, and K ir2.1, K ir2.3, and K ir2.4 as well as K v2.1. We conclude that osteoblasts express channels that allow firing of action potentials.
AB - Whole-cell patch-clamp analysis revealed a resting membrane potential of -60 mV in primary osteoblasts and in the MG-63 osteoblast-like cells. Depolarization-induced action potentials were characterized by duration of 60 ms, a minimal peak-to-peak distance of 180 ms, a threshold value of -20 mV and a repolarization between the spikes to -45 mV. Expressed channels were characterized by application of voltage pulses between -150 mV and 90 mV in 10 mV steps, from a holding potential of -40 mV. Voltages below -60 mV induced an inward current. Depolarizing voltages above -30 mV evoked two currents: (a) a fast activated and inactivated inward current at voltages between -30 and 30 mV, and (b) a delayed-activated outward current that was induced by voltages above -30 mV. Electrophysiological and pharmacological parameters indicated that hyperpolarization activated strongly rectifying K + (K ir) channels, whereas depolarization activated tetrodotoxin sensitive voltage gated Na + (Na v) channels as well as delayed, slowly activated, non-inactivating, and tetraethylammonium sensitive voltage gated K + (K v) channels. In addition, RT-PCR showed expression of Na v1.3, Na v1.4, Na v1.5, Na v1.6, Na v1.7, and K ir2.1, K ir2.3, and K ir2.4 as well as K v2.1. We conclude that osteoblasts express channels that allow firing of action potentials.
KW - Action potential
KW - K
KW - MG-63 cells
KW - Na
KW - Osteoblasts
KW - RT-PCR
UR - http://www.scopus.com/inward/record.url?scp=79959694144&partnerID=8YFLogxK
U2 - 10.1007/s10863-011-9354-7
DO - 10.1007/s10863-011-9354-7
M3 - Article
C2 - 21523406
AN - SCOPUS:79959694144
VL - 43
SP - 311
EP - 322
JO - Journal of Bioenergetics and Biomembranes
JF - Journal of Bioenergetics and Biomembranes
SN - 0145-479X
IS - 3
ER -