scholarly journals Comparison between low-level 50 Hz and 900 MHz electromagnetic stimulation on single channel ionic currents and on firing frequency in dorsal root ganglion isolated neurons

2006 ◽  
Vol 1758 (5) ◽  
pp. 597-605 ◽  
Author(s):  
I. Marchionni ◽  
A. Paffi ◽  
M. Pellegrino ◽  
M. Liberti ◽  
F. Apollonio ◽  
...  
Keyword(s):  
Dorsal Root Ganglion ◽  
Dorsal Root ◽  
Single Channel ◽  
Ionic Currents ◽  
Firing Frequency ◽  
Isolated Neurons ◽  
Low Level ◽  
Electromagnetic Stimulation

GABA-Induced Cl− Current in Cultured Embryonic Human Dorsal Root Ganglion Neurons

1999 ◽  
Vol 82 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Alexander Y. Valeyev ◽  
John C. Hackman ◽  
Alice M. Holohean ◽  
Patrick M. Wood ◽  
Jennifer L. Katz ◽  
...  
Keyword(s):  
Dorsal Root Ganglion ◽  
Dorsal Root ◽  
Single Channel ◽  
Dorsal Root Ganglion Neurons ◽  
Hill Coefficient ◽  
Equilibrium Potential ◽  
Single Channels ◽  
Drg Neurons ◽  
Whole Cell ◽  
Ganglion Neurons

γ-Aminobutyric acid (GABA)-activated channels in embryonic (5–8 wk old) human dorsal root ganglion (DRG) neurons in dissociated culture were characterized by whole cell and single-channel techniques. All DRG neurons when held at negative holding membrane potentials displayed inward current to micromolar concentrations of GABA applied by pressure pulses from closely positioned micropipettes. The current was directly proportional to the concentration of GABA (EC50, 111 μM; Hill coefficient, 1.7). DRG neurons also responded to micromolar concentrations of pentobarbital and alphaxalone but not to cis-4-aminocrotonic acid (CACA), glycine, or taurine. Baclofen (100 μM) affected neither the holding currents nor K+ conductance (when patch pipettes were filled with 130 mM KCl) caused by depolarizing pulses. Whole cell GABA-currents were blocked by bicuculline, picrotoxin, and t-butylbicyclophosphorothionate (TBPS; all at 100 μM). The reversal potential of whole cell GABA-currents was close to the theoretical Cl− equilibrium potential, shifting with changes in intracellular Cl− concentration in a manner expected for Cl−-selective channels. The whole cell I-V curve for GABA-induced currents demonstrated slight outward rectification with nearly symmetrical outside and inside Cl− concentrations. Spectral analysis of GABA-induced membrane current fluctuations showed that the kinetic components were best fitted by a triple Lorentzian function. The apparent elementary conductance for GABA-activated Cl− channels determined from the power spectra was 22.6 pS. Single-channel recordings from cell-attached patches with pipettes containing 10 μM GABA indicated that GABA-activated channels have a main and a subconductance level with values of 30 and 19 pS, respectively. Mean open and closed times of the channel were characterized by two or three exponential decay functions, suggesting two or three open channel states and two closed states. Single channels showed a lack of rectification. The actions of GABA on cultured human embryonic DRG neurons are mediated through the activation of GABAA receptors with properties corresponding to those found in the CNS of human and other mammalian species but differing from those of cultured human adult DRG neurons.

scholarly journals Effect of Low Level Laser Therapy on Chronic Compression of the Dorsal Root Ganglion

PLoS ONE ◽  
2014 ◽  
Vol 9 (3) ◽  
pp. e89894 ◽  
Author(s):  
Yi-Jen Chen ◽  
Yan-Hsiung Wang ◽  
Chau-Zen Wang ◽  
Mei-Ling Ho ◽  
Po-Lin Kuo ◽  
...  
Keyword(s):  
Dorsal Root Ganglion ◽  
Laser Therapy ◽  
Dorsal Root ◽  
Low Level Laser Therapy ◽  
Low Level ◽  
Low Level Laser ◽  
Level Laser

scholarly journals Selective internalization of sodium channels in rat dorsal root ganglion neurons infected with herpes simplex virus-1

2002 ◽  
Vol 158 (7) ◽  
pp. 1251-1262 ◽  
Author(s):  
Nina Storey ◽  
David Latchman ◽  
Stuart Bevan
Keyword(s):  
Herpes Simplex ◽  
Dorsal Root Ganglion ◽  
Sodium Channels ◽  
Dorsal Root ◽  
Dynamic Control ◽  
Ionic Currents ◽  
Dorsal Root Ganglion Neurons ◽  
Cell Protein ◽  
Viral Protein Synthesis ◽  
Ganglion Neurons

The neurotropic virus, herpes simplex type 1 (HSV-1), inhibits the excitability of peripheral mammalian neurons, but the molecular mechanism of this effect has not been identified. Here, we use voltage-clamp measurement of ionic currents and an antibody against sodium channels to show that loss of excitability results from the selective, precipitous, and complete internalization of voltage-activated sodium channel proteins from the plasma membrane of neurons dissociated from rat dorsal root ganglion. The internalization process requires viral protein synthesis but not viral encapsulation, and does not alter the density of voltage-activated calcium or potassium channels. However, internalization is blocked completely when viruses lack the neurovirulence factor, infected cell protein 34.5, or when endocytosis is inhibited with bafilomycin A1 or chloroquine. Although it has been recognized for many years that viruses cause cell pathology by interfering with signal transduction pathways, this is the first example of viral pathology resulting from selective internalization of an integral membrane protein. In studying the HSV-induced redistribution of sodium channels, we have uncovered a previously unknown pathway for the rapid and dynamic control of excitability in sensory neurons by internalization of sodium channels.

TREK-2 (K2P10.1) and TRESK (K2P18.1) are major background K+ channels in dorsal root ganglion neurons

2006 ◽  
Vol 291 (1) ◽  
pp. C138-C146 ◽  
Author(s):  
Dawon Kang ◽  
Donghee Kim
Keyword(s):  
Dorsal Root Ganglion ◽  
Dorsal Root ◽  
Single Channel ◽  
Active Role ◽  
Dorsal Root Ganglion Neurons ◽  
Pcr Analysis ◽  
Drg Neurons ◽  
Ganglion Neurons ◽  
Pore Domain ◽  
Inside Out

Dorsal root ganglion (DRG) neurons express mRNAs for many two-pore domain K+ (K2P) channels that behave as background K+ channels. To identify functional background K+ channels in DRG neurons, we examined the properties of single-channel openings from cell-attached and inside-out patches from the cell bodies of DRG neurons. We found seven types of K+ channels, with single-channel conductance ranging from 14 to 120 pS in 150 mM KCl bath solution. Four of these K+ channels showed biophysical and pharmacological properties similar to TRESK (14 pS), TREK-1 (112 pS), TREK-2 (50 pS), and TRAAK (73 pS), which are members of the K2P channel family. The molecular identity of the three other K+ channels could not be determined, as they showed low channel activity and were observed infrequently. Of the four K2P channels, the TRESK-like (14 pS) K+ channel was most active at 24°C. At 37°C, the 50-pS (TREK-2 like) channel was the most active and contributed the most (69%) to the resting K+ current, followed by the TRESK-like 14-pS (16%), TREK-1-like 112-pS (12%), and TRAAK-like 73-pS (3%) channels. In DRG neurons, mRNAs of all four K2P channels, as well as those of TASK-1 and TASK-3, were expressed, as judged by RT-PCR analysis. Our results show that TREKs and TRESK together contribute >95% of the background K+ conductance of DRG neurons at 37°C. As TREKs and TRESK are targets of modulation by receptor agonists, they are likely to play an active role in the regulation of excitability in DRG neurons.

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