CGS 21680 Hydrochloride (CGS 21680 HCl)(IC50=22 nM), an adenosine receptor agonist, exhibits 140-fold potency in A2 receptor over A1 receptor.

A2 receptor:22 nM

CGS 21680 HCl 是一种与腺苷A2受体高亲和力结合（Kd = 15.5 nM）的激动剂，IC50 值为 22 nM，对A1受体的选择性高出约140倍。在分离的灌注工作大鼠心脏模型中，CGS 21680C 能有效增加冠状动脉流量，其ED25值为1.8 nM。[1] 该化合物向腺苷A2受体的结合表现出高亲和性和有限的结合能力（表观Bmax = 375 fmol/mg蛋白），且仅识别一个类别的结合位点。[2] 在海马脑片中，CGS 21680作为对电生理活动的前突触和后突触测量（推测的A1受体介导事件）的弱激动剂，且在刺激cAMP形成（推测的A2介导响应）方面无效。在纹状体脑片中，CGS 21680能够强力刺激cAMP的形成，其EC50为110 nM，但在抑制电刺激下的多巴胺释放方面无效。[3]CGS 21680A为CGS 21680是盐酸盐形式，而CGS 21680C为CGS 21680的钠盐形式。

CGS 21680A 在自发性高血压大鼠中通过口服给药方式活跃，剂量为10 mg/kg，效力持续长达24小时。CGS 21680A 会引起心率短暂（60分钟）增加。[1]CGS 21680 是一种强效抑制剂，能够压制自发性、乙酰胆碱和谷氨酸诱导的大鼠大脑皮层神经元的放电。[4]

10×106 MNCs from each group are re-suspended in 2 mL RPMI 1640. Cell suspensions are added with carboxy-fluorescein diacetate, succinimidyl ester (CFSE, final concentration 2.5 μM) and thoroughly mixed. After incubation in the dark for 15 min at 37°C, the staining process is quenched by adding 10 mL ice-cold complete RPMI 1640 (containing 10% FBS) and incubated on ice for 5 min. Then cells are washed twice with RPMI 1640. Cell pellets are re-suspended in complete RPMI 1640 (containing 10% FBS). The stained MNCs (1×106 cells/mL, 1 mL/well) are cultured in triplicates in 24-well culture plates in the dark at 37°C. Each well is supplied with 50 μL of Concanavalin A (ConA, final concentration 5 μg/mL) or 50 μL of P0 peptide (final concentration 10 μg/mL). 72 h later, cells are collected and stained with PE-labeled anti-rat CD4 antibody for 30 min at 4°C. Finally, cells are analyzed with a flow cytometer.