Adenosine Receptor Data

Receptor Subtype A1 A2A A2B A3
Transduction Mechanism ↓Adenylyl Cyclase (Gi/o) and ↑ PLC ↑Adenylyl Cyclase (Gs) ↑Adenylyl Cyclase (Gs) and ↑ PLC (Gq) ↓Adenylyl Cyclase (Gi/o) and ↑ PLC
Primary Distribution Brain (cortex, cerebellum, hippocampus), spinal cord, eye, adrenal gland, atria Spleen, thymus, leukocytes, platelets, striatopallidal GABAergic neurons, olfactory bulb Cecum, colon, bladder Testis, mast cells
Tissue Function Antinociception, hypothermia, sedation, sleep, inhibition of lipolysis, cardio- and neuroprotection Reflex tachycardia, vasodilation, inhibition of platelet aggregation, sleep, protection against ischemia Relaxation of vascular and intestinal smooth muscle, cytokine production, inhibition of cell proliferation Mast cell degranulation, coronary vasodilation and protection from reperfusion
Key Compounds Ki Values (nM)
Agonists CGS 21680 (1063)
2-Chloro-N6-cyclopentyladenosine (1705)
2-Cl-IB-MECA (1104)
N6-Cyclopentyladenosine (1702)
HEMADO (1579)
IB-MECA (1066)
2'-MeCCPA (2281)
NECA (1691)
SDZ WAG 994 (2465)
290
0.8
820 (rat)
2.3
327
3.7
3.3
14
23
27
2300
470 (rat)
790
1230
2500
9580
20 -
88800*
18800*
-
18600*
100000*
11000*
37600
2400*
25000
67
42
0.33 (rat)
43
1.1
1.2
1150
6.2
-
Antagonists CGS 15943 (1699)
DPCPX (0439)
MRS 1220 (1217)
MRS 1334 (1385)
MRS 1706 (1584)
MRS 1754 (2752)
MRS 3777 (2403)
PSB 36 (2019)
SCH 442416 (2463)
VUF 5574 (1359)
ZM 241385 (1036)
8-(3-Chlorostyryl)caffeine (3306)
PSB 1115 (2009)
PSB 603 (3198)
3.5
3.9
305 (rat)
> 100000 (rat)
157
403
> 10000
0.12 (rat)
1111
~ 10000 (rat)
540
28200
> 10000
> 10000
4.2
130
52 (rat)
> 100000 (rat)
112
503
> 10000
552 (rat)
0.048
> 10000 (rat)
1.4
54
24000
> 10000
16
50
-
-
1.39
1.97
> 10000
187
> 10000
-
31
-
53.4
0.568
51
4000
0.7
5.69
230
570
47
2300
> 10000
4
270
-
> 10000
> 10000

* EC50 values

References

Klotz et al (2000) Naunyn-Schmied.Arch.Pharmacol. 362 382.Kim et al (1994) J.Med.Chem. 37 3614. van Muijlwijk-Koezen et al (2000) J.Med.Chem. 43 2227. Kim et al (2000) J.Med.Chem. 43 1165. Volpini et al (2002) J.Med.Chem. 45 3271. Li et al (1998) J.Med.Chem. 41 3186. Cappellacci et al (2005) J.Med.Chem. 48 1550. Osama et al (2004) J.Pharmacol.Exp.Ther. 308 358. Toddle et al (2000) J.Med.Chem. 43 4359. Jacobson and Gao (2000) Nat.Rev.Drug Discov. 5 247.