Modulation of cyclooxygenase-2 on glycine- and glutamate-induced ion currents in rat periaqueductal gray neurons.
Cyclooxygenase (COX) is a key enzyme in the conversion of arachidonic acid to prostaglandins. Two isoforms of COX are known: COX-1 and COX-2. In the present study, the modulatory effect of COX-2 on glycine- and glutamate-induced ion currents in periaqueductal gray (PAG) neurons was investigated using the nystatin-perforated patch clamp method. Continuous application of lipopolysaccharides on PAG neurons resulted in increased glycine-induced ion current and decreased glutamate-induced ion current. In contrast, continuous application of celecoxib, selective COX-2 inhibitor, resulted in decreased glycine-induced ion current and increased glutamate-induced ion current. These results demonstrate that COX-2 modulates neuronal activity of PAG, and it can be suggested that COX-2 participates in the regulation of the descending pain control system in the level of PAG neurons.
Shin
Min-Chul
MC
Department of Physiology, College of Medicine, Kyung Hee University, Seoul, South Korea.
Jang
Mi-Hyeon
MH
Chang
Hyun-Kyung
HK
Kim
Youn-Jung
YJ
Kim
Ee-Hwa
EH
Kim
Chang-Ju
CJ
D000818:Animals; D000068579:Celecoxib; D051546:Cyclooxygenase 2; D052246:Cyclooxygenase 2 Inhibitors; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology; D005260:Female; D018698:Glutamic Acid / Q000494:pharmacology; D005998:Glycine / Q000494:pharmacology; D017136:Ion Transport / Q000187:drug effects; D007527:Isoenzymes / Q000187:drug effects / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology*; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D018408:Patch-Clamp Techniques; D010487:Periaqueductal Gray / Q000378:metabolism; D011451:Prostaglandin-Endoperoxide Synthases / Q000187:drug effects / Q000378:metabolism*; D011720:Pyrazoles; D051381:Rats; D017207:Rats, Sprague-Dawley; D013449:Sulfonamides / Q000494:pharmacology
D052246:Cyclooxygenase 2 Inhibitors; D016861:Cyclooxygenase Inhibitors; D007527:Isoenzymes; D008070:Lipopolysaccharides; D011720:Pyrazoles; D013449:Sulfonamides; D018698:Glutamic Acid; D051546:Cyclooxygenase 2; D011451:Prostaglandin-Endoperoxide Synthases; D000068579:Celecoxib; D005998:Glycine