新型阿片受体配基特异性结合μ受体并抑制cAMP生成  

Specific binding to μopioid receptors by new opioid ligands with inhibition of I cAMP production

作　　者：胡萍[1] 叶菜英[1] 仇缀佰[2] 杨惠芬[1] 张德昌[1] 

机构地区：[1]中国医学科学院中国协和医科大学基础医学研究所药理室,北京100005 [2]复旦大学药学院,上海200032

出　　处：《基础医学与临床》2003年第5期494-498,共5页Basic and Clinical Medicine

基　　金：国家自然科学基金 (396 30 12 0 );国家自然科学基金海外青年学者合作基金 (3992 80 17)

摘　　要：本文研究新合成阿片受体配基对稳定表达 μ阿片受体的CHO细胞的受体结合特性和对胞内cAMP的抑制作用。采用放射性配基结合的方法研究了阿片受体配基 [3H] diprenorphine(3H dip)在稳定表达 μ阿片受体的CHO细胞模型上 ,对 μ阿片受体的饱和性结合特征及和一系列新合成阿片配基A、B、C、D、E、F、G、及DAMGO([D Ala ,N Me Phe4 ,Gly ol5] enkephalin)和吗啡的竞争性结合特征。利用竞争性结合蛋白法测定阿片受体配基对胞内cAMP的抑制作用。 [3H] diprenorphine结合 μ阿片受体的Kd值为 1 0 6nmol L ;Bmax为 930fmol mg蛋白。结果表明新配基、DAMGO和吗啡竞争性结合 μ受体的IC50 值分别为 13 33± 3 73、14 36± 1 5 8、0 6 2± 0 0 3、5 6 38± 2 33、6 5 72±2 6 4 4、33 10± 11 33、0 5 5± 0 0 6、3 6 9± 1 5 9和 1 83± 0 5 0。其中C和G配基对 μ阿片受体的亲和力高于DAMGO和吗啡。B、D、E和F配基对μ受体的亲和力低于DAMGO和吗啡。新配基、DAMGO和吗啡抑制cAMP生成的IC50 值分别为 6 4 9± 1 5 9、1390± 6 1 10、0 84± 0 11、2 33± 1 2 4、2 5 0 0± 17 2 0、1 4 2± 1 2 1、0 0 1± 0 0 1、0 10± 0 0 5和0 0 4± 0 0 1。其中G配基的抑制胞内cAMP作用最强 ,强于吗啡 。To determine the affinity of new opioid receptor ligands to cloned μ opioid receptors stably expressed in CHO cell and measurement of the ligands inhibition of intracellular cAMP level. The binding characteristics of the opioid ligand diprenorphine were studied by radioligands binding in cloned δ opioid receptors stably expressed in Chinese hamster ovary cells in saturation binding experiments, and then followed by competition binding experiments with a variety of new opioid receptor ligands A, B, C, D, E, F, G, DAMGO ([D Ala 2, N Me Phe 4, Gly ol 5] enkephalin and Morphine. The opioid ligands inhibition of intracellular cAMP production was determined. diprenorphine bound to a larger population of mu receptors (Kd, 1.06; Bmax 930 fmol/mg protein ). Competition binding experiments revealed that IC 50 values of the new ligands, DAMGO and Morphine were 13.33 ±3.73, 14.36 ±1.58, 0.62 ±0.03, 56.38±2.33, 65.72±26.44, 33.10±11.33, 0.55±0.06, 3.69±1.59 and 1.83±0.50 respectively. Ligand C, G displayed much higher affinity than DAMGO and Morphine( P <0.05). However, the affinity of ligand A, B,D, E,F were lower than that of DAMGO and Morphine. IC 50 values of the new ligands, that of DAMGO and Morphine in inhibiting forskolin-stimulated production of intracellular cAMP were 6.49 ±1.59, 1390 ±61.10, 0.84 ±0.11, 2.33±1.24, 25.00±17.20, 1.42±1.21, 0.01±0.01, 0.10±0.05 and 0.04±0.01 respectively. Ligand G possesses the highest potency in inhibiting forsklin stimulated conversion to cAMP, higher than Morphine. Ligand A,C,D and E were similar to DAMGO and Morphine. The results suggest that the new ligands have good affinity to μ opioid receptors and inhibit intracellular cAMP production.

关 键 词：阿片受体配基 Μ受体 CAMP 受体结合 CHO细胞 阿片类药物 

分 类 号：R96[医药卫生—药理学]