Protein kinase C inhibitor potentiates the agonist-induced GTPase activity in COS cell membranes expressing delta-opioid receptor.
In COS-7 cell membranes expressing cloned delta-opioid receptor, [D-Ser2, Leu5]enkephalin-Thr6, an opioid delta-agonist, showed no significant stimulation of high-affinity GTPase, while this agonist binding showed a guanine nucleotide sensitivity. Significant stimulation of GTPase activity by this agonist was observed only when the cells were pretreated with 0.1 microM calphostin C, a protein kinase C inhibitor, and when this inhibitor was further added to the reaction mixture at 1 microM. These findings suggest that protein kinase C is involved in the heterologous desensitization of delta-opioid receptor in the cells.
Hayashi
C
C
Department of Pharmacology, Yokohama City University School of Medicine, Japan.
Ueda
H
H
Fukushima
N
N
Katayama
T
T
Misu
Y
Y
D000700:Analgesics / Q000494:pharmacology; D000818:Animals; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D002522:Chlorocebus aethiops; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D004743:Enkephalin, Leucine / Q000031:analogs & derivatives* / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D020558:GTP Phosphohydrolases / Q000378:metabolism*; D016244:Guanosine 5'-O-(3-Thiotriphosphate) / Q000494:pharmacology; D006160:Guanosine Triphosphate / Q000494:pharmacology; D007668:Kidney; D007700:Kinetics; D009281:Naphthalenes / Q000494:pharmacology*; D011493:Protein Kinase C / Q000037:antagonists & inhibitors*; D017465:Receptors, Opioid, delta / Q000096:biosynthesis / Q000502:physiology*; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000378:metabolism; D014162:Transfection
D000700:Analgesics; D004791:Enzyme Inhibitors; D009281:Naphthalenes; D017465:Receptors, Opioid, delta; D011994:Recombinant Proteins; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D004743:Enkephalin, Leucine; C034318:enkephalin, Ser(2), Leu(5), Thr(6)-; D006160:Guanosine Triphosphate; D011493:Protein Kinase C; D020558:GTP Phosphohydrolases; C058819:calphostin C