Abstract
Single Na+ channel currents were recorded from cell-attached membrane patches from two neuronal cell lines derived from rat brain, B50 and B104, and compared before and after exposure of the cells to purified brevetoxin, PbTx-3. B50 and B104 Na+ channels usually exhibited fast activation and inactivation as is typical of TTX-sensitive Na+ channels. PbTx-3 modified channel gating in both cell lines. PbTx-3 caused (1) significant increases in the frequency of channel reopening, indicating a slowing of channel inactivation, (2) a change in the voltage dependence of the channels, promoting channel opening during steady-state voltage clamp of the membrane at voltages throughout the activation range of Na+ currents, but notably near the resting potential of these cells (-60 - -50 mV), and (3) a significant, 6.7 mV hyperpolarized shift in the threshold potential for channel opening. Na+ channel slope conductance did not change in PbTx-3- exposed B50 and B104 neurons. These effects of Pbx-3 may cause hyperexcitability as well as inhibitory effects in intact brain. (C) 1999 Intox Press, Inc.
| Original language | English |
|---|---|
| Pages (from-to) | 909-920 |
| Number of pages | 12 |
| Journal | NeuroToxicology |
| Volume | 20 |
| Issue number | 6 |
| State | Published - Dec 1 1999 |
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Keywords
- Brevetoxin
- Cell Lines
- Na Channel
- Neurotoxic Shellfish Poisoning
- Patch Clamp
- Single Channel
ASJC Scopus subject areas
- Cellular and Molecular Neuroscience
- Neuroscience(all)
- Toxicology
Cite this
Brevetoxin modulates neuronal sodium channels in two cell lines derived from rat brain. / Purkerson, S. L.; Baden, D. G.; Fieber, Lynne A.
In: NeuroToxicology, Vol. 20, No. 6, 01.12.1999, p. 909-920.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Brevetoxin modulates neuronal sodium channels in two cell lines derived from rat brain
AU - Purkerson, S. L.
AU - Baden, D. G.
AU - Fieber, Lynne A
PY - 1999/12/1
Y1 - 1999/12/1
N2 - Single Na+ channel currents were recorded from cell-attached membrane patches from two neuronal cell lines derived from rat brain, B50 and B104, and compared before and after exposure of the cells to purified brevetoxin, PbTx-3. B50 and B104 Na+ channels usually exhibited fast activation and inactivation as is typical of TTX-sensitive Na+ channels. PbTx-3 modified channel gating in both cell lines. PbTx-3 caused (1) significant increases in the frequency of channel reopening, indicating a slowing of channel inactivation, (2) a change in the voltage dependence of the channels, promoting channel opening during steady-state voltage clamp of the membrane at voltages throughout the activation range of Na+ currents, but notably near the resting potential of these cells (-60 - -50 mV), and (3) a significant, 6.7 mV hyperpolarized shift in the threshold potential for channel opening. Na+ channel slope conductance did not change in PbTx-3- exposed B50 and B104 neurons. These effects of Pbx-3 may cause hyperexcitability as well as inhibitory effects in intact brain. (C) 1999 Intox Press, Inc.
AB - Single Na+ channel currents were recorded from cell-attached membrane patches from two neuronal cell lines derived from rat brain, B50 and B104, and compared before and after exposure of the cells to purified brevetoxin, PbTx-3. B50 and B104 Na+ channels usually exhibited fast activation and inactivation as is typical of TTX-sensitive Na+ channels. PbTx-3 modified channel gating in both cell lines. PbTx-3 caused (1) significant increases in the frequency of channel reopening, indicating a slowing of channel inactivation, (2) a change in the voltage dependence of the channels, promoting channel opening during steady-state voltage clamp of the membrane at voltages throughout the activation range of Na+ currents, but notably near the resting potential of these cells (-60 - -50 mV), and (3) a significant, 6.7 mV hyperpolarized shift in the threshold potential for channel opening. Na+ channel slope conductance did not change in PbTx-3- exposed B50 and B104 neurons. These effects of Pbx-3 may cause hyperexcitability as well as inhibitory effects in intact brain. (C) 1999 Intox Press, Inc.
KW - Brevetoxin
KW - Cell Lines
KW - Na Channel
KW - Neurotoxic Shellfish Poisoning
KW - Patch Clamp
KW - Single Channel
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UR - http://www.scopus.com/inward/citedby.url?scp=0033380890&partnerID=8YFLogxK
M3 - Article
C2 - 10693972
AN - SCOPUS:0033380890
VL - 20
SP - 909
EP - 920
JO - NeuroToxicology
JF - NeuroToxicology
SN - 0161-813X
IS - 6
ER -