Ma L, Cheng Z J, Fan G H, Cai Y C, Jiang L Z, Pei G
Department of Neurobiology, Shanghai Medical University, People's Republic of China.
FEBS Lett. 1997 Feb 10;403(1):91-4. doi: 10.1016/s0014-5793(97)00031-8.
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.
已对神经母细胞瘤x胶质瘤NG108 - 15杂交细胞进行了阿片样受体样受体（ORL1）表达的检测。[3H]孤啡肽/孤啡肽FQ（OFQ）特异性结合于细胞膜（解离常数Kd = 3.6±0.6 nM），并抑制福斯高林刺激的环磷酸腺苷（cAMP）积累（半数有效浓度EC50 = 0.72±0.3 nM）。百日咳毒素可阻断NG108 - 15细胞对孤啡肽/OFQ的反应，但纳曲吲哚不能。用相同肽预刺激后，孤啡肽/OFQ的抑制活性显著降低，但不受D - 丙氨酸 - D - 苯丙氨酸 - D - 缬氨酸 - D - 苯丙氨酸乙酯（DPDPE）预处理的影响，表明ORL1受体存在急性和同源脱敏现象。纳曲吲哚在DPDPE预处理的细胞中引起cAMP超调，但在孤啡肽/OFQ预处理的细胞中未引起。结果表明，ORL1在功能上有表达，且在NG108 - 15细胞中不与δ阿片受体的特异性配体发生交叉相互作用。
