Functional expression, activation and desensitization of opioid receptor-like receptor ORL1 in neuroblastoma x glioma NG108-15 hybrid cells.
Neuroblastoma x glioma NG108-15 hybrid cells have been examined for the expression of opioid receptor-like receptor (ORL1). [3H]Nociceptin/orphanin FQ (OFQ) bound to the cell membrane specifically (Kd = 3.6 +/- 0.6 nM) and inhibited forskolin-stimulated cAMP accumulation (EC50 = 0.72 +/- 0.3 nM). The responsiveness of NG108-15 cells to nociceptin/OFQ was blocked by pertussis toxin but not by naltrindole. The inhibitory activity of nociceptin/OFQ was significantly reduced after a prechallenge with the same peptide but was not influenced by DPDPE pretreatment, indicating acute and homologous desensitization of ORL1 receptors. Naltrindole caused the overshoot of cAMP in DPDPE-pretreated cells but not in nociceptin/OFQ-pretreated cells. The results indicate that ORL1 is functionally expressed and does not cross-interact with specific ligands of the delta opioid receptor in NG108-15 cells.
Ma
L
L
Department of Neurobiology, Shanghai Medical University, People's Republic of China.
Cheng
Z J
ZJ
Fan
G H
GH
Cai
Y C
YC
Jiang
L Z
LZ
Pei
G
G
D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism; D020881:Enkephalin, D-Penicillamine (2,5)-; D004745:Enkephalins / Q000494:pharmacology; D019204:GTP-Binding Proteins / Q000187:drug effects / Q000378:metabolism; D005910:Glioma / Q000188:drug therapy / Q000378:metabolism*; D006822:Hybrid Cells / Q000187:drug effects / Q000378:metabolism*; D009271:Naltrexone / Q000031:analogs & derivatives / Q000494:pharmacology; D009292:Narcotic Antagonists / Q000494:pharmacology; D009447:Neuroblastoma / Q000188:drug therapy / Q000378:metabolism*; D018847:Opioid Peptides / Q000378:metabolism / Q000494:pharmacology*; D037342:Pertussis Toxin; D011957:Receptors, Opioid / Q000187:drug effects / Q000378:metabolism*; D017465:Receptors, Opioid, delta / Q000378:metabolism; D010566:Virulence Factors, Bordetella / Q000494:pharmacology; D000094942:Nociceptin Receptor; D000097629:Nociceptin
D005576:Colforsin; D000242:Cyclic AMP; D020881:Enkephalin, D-Penicillamine (2,5)-; D004745:Enkephalins; D019204:GTP-Binding Proteins; D009271:Naltrexone; D009292:Narcotic Antagonists; D018847:Opioid Peptides; D037342:Pertussis Toxin; D011957:Receptors, Opioid; D017465:Receptors, Opioid, delta; D010566:Virulence Factors, Bordetella; D000094942:Nociceptin Receptor; D000097629:Nociceptin; C055382:naltrindole