Effects of ropivacaine on GABA-activated currents in isolated dorsal root ganglion neurons in rats / 中国应用生理学杂志
Chinese Journal of Applied Physiology
; (6): 263-266, 2013.
Article
in Zh
| WPRIM
| ID: wpr-235384
Responsible library:
WPRO
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the effects of ropivacaine on Gamma-aminobutyric acid(GABA)-activated currents in dorsal root ganglion (DRG) neurons in rats and discuss the analgesia mechanism of ropivacaine.</p><p><b>METHODS</b>By means of using whole-cell patch-clamp technique, to investigate the modulatory effects of ropivacaine on GABA-activated currents (I(GABA)) in acutely isolated dorsal root ganglion neurons.</p><p><b>RESULTS</b>(1) In 48 out of 73DRG cells (65.7%, 48/73), to perfusion ropivacaine bromide (0.1 - 1 000 micromol/L) were sensitive. Which produce in 0 to 380 pA current. (2) The majority of the neurons examined (74.5%, 73/98) were sensitive to GABA. Concentration of 1 - 1 000 micromol/L GABA could activate a concentration-dependent inward current, which manifested obvious desensitization, and the inward currents could be blocked byGABA-receptor selective antagonist of bicuculline (100 micromol/L). (3) After the neurons were treated with ropivacaine (0.1 - 1000 micromol/L) prior to the application of GABA (100 micromol/L) 30 s, GABA currents were obviously increased. Ropivacaine could make dose-response curve of the GABA up, EC50 is 23.46 micromol/L. Ropivacaine shifted the GABA dose-response curve upward and increased the maximum response to the contrast about 153%.</p><p><b>CONCLUSION</b>The enhancement of ropivacaine to DRG neurons activation of GABA current, can lead to enhancement of pre-synaptic inhibition at the spinal cord level. This may be one of the reasons for the anesthetic effect and analgesia for ropivacaine in epidural anesthesia.</p>
Full text:
1
Index:
WPRIM
Main subject:
Pharmacology
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Physiology
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Rats, Sprague-Dawley
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Receptors, GABA-A
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Patch-Clamp Techniques
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Cell Biology
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Amides
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Ganglia, Spinal
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Membrane Potentials
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Neurons
Limits:
Animals
Language:
Zh
Journal:
Chinese Journal of Applied Physiology
Year:
2013
Type:
Article