MgCl2和Gpp（NH）p对腺苷A1受体激动剂和拮抗剂结合的作用比较（英文）

作     者：Keith FINLAYSON,MAEMOTO Takuya,Steven P BUTCHER,John SHARKEY,Henry J OLVERMAN 

作者机构：Fujisawa Institute of Neuroscience Fujisawa Institute of Neuroscience Fujisawa Institute of Neuroscience Division of Neuroscience University of Edinburgh Level 6 Appleton Tower Crichton Street. Edinburgh EH8 9LE UK Division of Neuroscience University of Edinburgh Level 6 Appleton Tower Crichton Street. Edinburgh EH8 9LE UK 

出 版 物：《Acta Pharmacologica Sinica》 (中国药理学报(英文版))

年 卷 期：2003年第24卷第8期

页      面：3-14+110页

核心收录：

学科分类：1007[医学-药学(可授医学、理学学位)] 1006[医学-中西医结合] 100706[医学-药理学] 100602[医学-中西医结合临床] 10[医学] 

主　　题：嘌呤P1受体 放射配位体测定 氯化镁 鸟苷酰亚氨二磷酸 脑 

摘      要：AIM: To investigate modulation of antagonist and agonist binding to adenosine A1receptors by MgCl2and 5 -guanylimidodiphosphate (Gpp（NH）p) using rat brain membranes and the A1antagonist [3H]-8-cyclopentyl-1,3-dipropylxanthine （[3H]DPCPX） and the A1agonist [3H]-2-chloro-N6-cyclopentyladenosine （[3H]CCPA）. METHODS: Parallel saturation and inhibition studies were performed using well-characterised radioligand binding assays and a Brandel Cell Harvester. RESULTS: MgCl2produced a concentration-dependent decrease （44%）, whereas Gpp（NH）p increased [3H]DPCPX binding （19%）. In [3H]DPCPX competition studies, agonist affinity was 1.5-14.6-fold higher and 4.6-10-fold lower in the presence of 10 mmol/L MgCl2and 10 μmol/L Gpp（NH）p respectively; antagonist affinity was unaffected. The decrease in agonist affinity with increasing Gpp（NH）p concentrations was due to a reduction in the proportion of binding to the high affinity receptor state. In contrast to [3H]DPCPX, MgCl2produced a concentration-