Bruns R F, Fergus J H, Badger E W, Bristol J A, Santay L A, Hartman J D, Hays S J, Huang C C
Naunyn Schmiedebergs Arch Pharmacol. 1987 Jan;335(1):59-63. doi: 10.1007/BF00165037.
8-Cyclopentyl-1,3-dipropylxanthine (PD 116,948) is a very potent, very A1-selective adenosine antagonist, with a Ki of 0.46 nM in 3H-CHA binding to A1 receptors in rat whole brain membranes and 340 nM in 3H-NECA binding to A2 receptors in rat striatal membranes. Its 740-fold A1-selectivity is the highest reported for an adenosine antagonist. 3H-PD 116,948 (117 Ci/mmol) was prepared by reduction of the diallyl analog. 3H-PD 116,948 bound to a single site in rat whole brain membranes, with a Bmax of 46 pmol/g wet weight and Kd of 0.42 nM. Nonspecific binding was extremely low, amounting to about 3% of total binding under standard conditions and less than 1% when higher tissue concentrations were used. Affinities of compounds for inhibition of 3H-PD 116,948 binding were highly consistent with an A1 adenosine receptor. Antagonists were equally potent in 3H-PD 116,948 binding and in 3H-CHA binding, while agonists were consistently about 12-fold more potent in 3H-CHA binding. Hill coefficients were 1.0 for antagonists and about 0.65 for agonists. 3H-PD 116,948 should be a useful antagonist ligand for adenosine A1 receptors.
8-环戊基-1,3-二丙基黄嘌呤（PD 116,948）是一种强效、高A1选择性的腺苷拮抗剂，在大鼠全脑膜中与A1受体的3H-CHA结合的Ki为0.46 nM，在大鼠纹状体膜中与A2受体的3H-NECA结合的Ki为340 nM。其740倍的A1选择性是已报道的腺苷拮抗剂中最高的。3H-PD 116,948（117 Ci/mmol）通过二烯丙基类似物的还原制备。3H-PD 116,948与大鼠全脑膜中的单一位点结合，Bmax为46 pmol/g湿重，Kd为0.42 nM。非特异性结合极低，在标准条件下约占总结合的3%，当使用更高的组织浓度时不到1%。化合物对3H-PD 116,948结合的抑制亲和力与A1腺苷受体高度一致。拮抗剂在3H-PD 116,948结合和3H-CHA结合中的效力相同，而激动剂在3H-CHA结合中的效力始终约高12倍。拮抗剂的希尔系数为1.0，激动剂约为0.65。3H-PD 116,948应该是一种用于腺苷A1受体的有用拮抗剂配体。
