Role of protein kinase C in opioid modulation of glycine-gated Cl(-) current in rat periaqueductal gray neuron.
The Role of protein kinase C in the modulatory effect of a mu-opioid receptor agonist, [D-Ala(2),N-Me-Phe(4),Gly(5)-ol]enkephalin (DAMGO), on the glycine-gated Cl(-) current was examined in acutely dissociated rat periaqueductal gray neurons. Using the nystatin-perforated patch-clamp technique, the neurons were voltage-clamped at -60 mV. The glycine-gated Cl(-) current (I(Gly)) was sensitive to strychnine. On pretreatment with 1 microM DAMGO, the 30-microM glycine response increased with time and showed a maximum amplitude of 209+/-37% of control. After a protein kinase C activator, phorbol-12-myristate-13-acetate (PMA, 0.1 microM) as pretreatment, I(Gly) increased to 138+/-6% of control. The DAMGO potentiation of I(Gly) was not altered by coapplication with PMA. Although protein kinase C inhibitors, chelerythrine (3 microM) and 2-[1-(3-dimethylaminopropyl)indol-3-yl]-3-(indol-3-yl) maleimide (GF109203X, 1 microM), did not alter I(Gly), the DAMGO-induced potentiation of I(Gly) was reduced to 161+/-21% or 164+/-31% of the control after coapplication with chelerythrine or GF109203X, respectively. These results indicate that the potentiation of I(Gly) by a mu-opioid receptor agonist is partly mediated by activation of protein kinase C.
Jeong
H J
HJ
Department of Physiology, College of Medicine, Kyung Hee University, Seoul 130-701, South Korea.
Lee
J J
JJ
Hahm
E T
ET
Han
S H
SH
Min
B I
BI
Cho
Y W
YW
D000470:Alkaloids; D000818:Animals; D053119:Benzophenanthridines; D002478:Cells, Cultured; D002712:Chlorides / Q000378:metabolism*; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)- / Q000494:pharmacology; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005998:Glycine / Q000378:metabolism*; D007211:Indoles / Q000494:pharmacology; D008301:Maleimides / Q000494:pharmacology; D009294:Narcotics / Q000378:metabolism*; D009474:Neurons / Q000378:metabolism; D009761:Nystatin; D018408:Patch-Clamp Techniques; D010487:Periaqueductal Gray / Q000378:metabolism*; D010617:Phenanthridines / Q000494:pharmacology; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000378:metabolism*; D051381:Rats; D017450:Receptors, Opioid, mu / Q000819:agonists*
D000470:Alkaloids; D053119:Benzophenanthridines; D002712:Chlorides; D004791:Enzyme Inhibitors; D007211:Indoles; D008301:Maleimides; D009294:Narcotics; D010617:Phenanthridines; D017450:Receptors, Opioid, mu; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; D009761:Nystatin; C016299:chelerythrine; D011493:Protein Kinase C; C070515:bisindolylmaleimide I; D005998:Glycine