Inhibition of P2X receptor-mediated inward current by protein kinase C in small-diameter dorsal root ganglion neurons of adult rats.
OBJECTIVE
The aim of the present study is to verify the ATP-induced varied responses in isolated dorsal root ganglion (DRG) neurons of the adult rat, and investigate the modulatory effects of specific P2X receptor agonist beta, gamma-me-ATP and protein kinase C (PKC) on P2X receptor-mediated inward current in DRG neurons.


METHODS
Whole cell patch-clamp was employed to record the currents on acutely isolated DRG neurons in the adult rats.


RESULTS
beta, gamma-me-ATP, similar as ATP, evoked 2 distinct subtypes of P2X receptor-mediated inward currents in a dose-dependent manner in DRG neurons. Activation of PKC by phorbol 12, 13-dibutyrate (PDBu) significantly inhibited both subtypes of inward currents mediated by P2X receptors in a dose-dependent manner.


CONCLUSIONS
Activation of PKC negatively modulated the P2X receptor-mediated currents in rat DRG neurons, which may be of benefit to preventing the over-excitation of nociceptor under inflammatory or neuropathic conditions.
Bie
Bi-Hua
BH
Institute of Neurobiology, Institutes of Brain Science and State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai 200032, China.
Zhang
Yi-Hong
YH
Zhao
Zhi-Qi
ZQ
D000255:Adenosine Triphosphate / Q000031:analogs & derivatives / Q000494:pharmacology; D000704:Analysis of Variance; D000818:Animals; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D004558:Electric Stimulation / Q000379:methods; D004789:Enzyme Activation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005727:Ganglia, Spinal / Q000166:cytology*; D007211:Indoles / Q000494:pharmacology; D008297:Male; D008301:Maleimides / Q000494:pharmacology; D008564:Membrane Potentials / Q000187:drug effects* / Q000502:physiology; D009474:Neurons / Q000145:classification / Q000187:drug effects* / Q000502:physiology; D018408:Patch-Clamp Techniques / Q000379:methods; D015240:Phorbol 12,13-Dibutyrate / Q000494:pharmacology; D011493:Protein Kinase C / Q000378:metabolism / Q000494:pharmacology*; D058910:Purinergic P2 Receptor Agonists; D058919:Purinergic P2 Receptor Antagonists; D051381:Rats; D017207:Rats, Sprague-Dawley; D018048:Receptors, Purinergic P2 / Q000502:physiology; D058476:Receptors, Purinergic P2X2; D013942:Thymine Nucleotides / Q000494:pharmacology
D004791:Enzyme Inhibitors; D007211:Indoles; D008301:Maleimides; C546403:P2rx2 protein, rat; D058910:Purinergic P2 Receptor Agonists; D058919:Purinergic P2 Receptor Antagonists; D018048:Receptors, Purinergic P2; D058476:Receptors, Purinergic P2X2; D013942:Thymine Nucleotides; D015240:Phorbol 12,13-Dibutyrate; C041083:beta, gamma-methylenedeoxythymidine 5'-triphosphate; C045674:2',3'-O-(2,4,6-trinitro-cyclohexadienylidine)adenosine 5'-triphosphate; D000255:Adenosine Triphosphate; D011493:Protein Kinase C; C088060:bisindolylmaleimide