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. Author manuscript; available in PMC: 2022 Aug 19.
Published in final edited form as: Pharmacol Rev. 2001 Dec;53(4):527–552.

TABLE 8.

Binding affinity of agonists and antagonists at rat adenosine receptor subtypes (Ki values with 95% confidence intervals or ±S.E.M. in parentheses)

A1 A2A A3 Reference
Agonists with unmodified ribose
R-PIA 1.2 (±0.16) 124 (±9) a
1.3 (1.1–1.6) 730 (690–770) b
0.51 c
220 (±43) d
160 (±52) e
S-PIA 49 (±2.4) 1,800 (±380) a
29 f
920 (±310) e
 CPA 0.59 (±0.02) 460 (±15) a
0.8 (0.6–1.0) 2,000 (1,400–2,900) b
240 (±36) e
 CCPA 0.4 (0.2–0.7) 3,900 (2,500–4,700) b
0.23 c
240 (±71) e
 ADAC 0.85 (±0.35) w
 2-Cl-adenosine 9.3 (±0.58) 63 (±7.5) a
1,900 (±900) e
 DPMA 140 (±23) 4.4 (±0.2) u
3,600 (±1,700) e
 (S)-ENBA 0.3 (±0.02) 1,400 (±150) v
Agonists with 5_-modified ribose
 NECA 6.3 (±0.52) 10 (±0.5) a
11 (7.0–17) 22 (20–25) f
3.7 c
260 (±36) d
 CGS 21680 3100 (±470) 22 (±4.3) g
580 (±32) e
 HENECA 136 (95–195) 3.8 (1.5–9.9) f
 PENECA 698 (611–798) 120 (112–128) h
 PHPNECA 2.5 (2.2–2.9) 0.9 (0.7–1.3) i
 AB-MECA 430 (±45) 1,600 (±180) 14 (±3) j
 IB-MECA 54 (±5) 56 (±8) 1.1 (±0.3) j
 IAB-MECA 18 (±5) 200 (±84) 1.3 (±0.18) j
 Cl-IB-MECA 820 (±570) 470 (±370) 0.33 (±0.08) k
Antagonists: xanthines
 DPCPX 0.3 340 l
0.18* (0.16–0.20) l
>10,000 e
 XAC 2.8 (1.9–4.2) m
3.5 24 l
4 50 n
>100,000 o
 MRS1754 17 (±3.6) 610 (±290) o
 MSX-2 900 (±10) 8 (±3) p
 Theophylline 11,000 32,000 b
>100,000 o
Antagonists: non-xanthines
 CGS 15943 21 (±3.5) 3.3 (±1.8) q
22 3 n
6.4 (6.2–6.6) 1.2 (1.1–1.3) r
>100,000 o
 SCH 58261 120 (100–140) 2.3 (2.0–2.7) r
 ZM 241385 2,000 (1,500–2,700) 0.30 (0.10–0.95) 150,000 (87,000–210,000) s
 MRE 3008F20 >10,000 2,000 (±220) >10,000 t
*

Data from saturation experiments; where confidence limits are missing, they are within 0.15 log units.

a

Bruns et al., 1986; brain membranes (A1), striatum (A2A); radioligands [3H]CHA (A1), [3H]NECA (A2A).

b

Lohse et al., 1988; brain membranes (A1), striatum (A2A); radioligands [3H]PIA (A1), [3H]NECA (A2A).

c

Klotz et al., 1991; brain membranes; radioligand [3H]DPCPX.

d

Olah et al., 1994; transfected CHO cells; radioligand 125I-AB-MECA.

e

van Galen et al., 1994; transfected CHO cells; radioligand 125I-APNEA.

f

Cristalli et al., 1992; brain membranes (A1), striatum (A2A); radioligands [3H]DPCPX (A1), [3H]NECA (A2A).

g

Hutchison et al., 1989; rat brain; radioligands [3H]CHA (A1), [3H]NECA (A2A). Given are IC50 values; based on the experimental conditions Ki values should be about 0.5– 0.7 and 0.9 times the IC50 values for A1 and A2A, respectively.

h

Cristalli et al., 1995; brain membranes (A1), striatum (A2A); radioligands [3H]CHA (A1), [3H]CGS 21680 (A2A).

i

Camaioni et al., 1997; brain membranes (A1), striatum (A2A); radioligands [3H]CHA (A1), [3H]CGS 21680 (A2A).

j

Gallo-Rodriguez et al., 1994; rat brain (A1), rat striatum (A2A), transfected CHO cells (A3); radioligand [3H]PIA (A1), [3H]CGS 21680 (A2A), 125I-AB-MECA (A3).

k

Kim et al., 1994; rat brain (A1), rat striatum (A2A), transfected CHO cells (A3); radioligand [3H]PIA (A1), [3H]CGS 21680 (A2A), 125I-AB-MECA (A3).

l

Lohse et al., 1987; brain membranes (A1), striatum (A2A); radioligands [3H]PIA (A1), [3H]NECA (A2A).

m

Jacobson et al., 1986; rat brain, radioligand [3H]XAC.

n

Jarvis et al., 1989; rat brain; radioligands [3H]CHA (A1), [3H]CGS 21680 (A2A).

o

Kim et al., 2000; transfected HEK 293 cells (A1), rat striatum (A2A); radioligands [3H]PIA (A1), [3H]CGS 21680 (A2A).

p

Sauer et al., 2000; brain cortex (A1), striatum (A2A); radioligand [3H]CHA (A1), [3H]CGS 21680 (A2A).

q

Williams et al., 1987; brain (A1), striatum (A2A); radioligands [3H]CHA (A1), [3H]NECA (A2A). Given are IC50 values; based on the experimental conditions Ki values should be about 0.5– 0.7 and 0.9 times the IC50 values for A1 and A2A, respectively.

r

Baraldi et al., 1994; rat brain (A1), rat striatum (A2A); radioligand [3H]CHA (A1), [3H]CGS 21680 (A2A).

s

Poucher et al., 1995; brain cortex (A1), PC 12 cells (A2A), transfected CHO cells (A3); radioligands [3H]PIA (A1), [3H]NECA (A2A) 125I-AB-MECA (A3). Given are IC50 values; based on the experimental conditions Ki values should be about 0.1, 0.2, and 0.5 times the IC50 values for A1, A2A, and A3, respectively.

t

Varani et al., 2000; brain cortex (A1), striatum (A2A), transfected CHO cells (A3); radioligands [3H]DPCPX (A1), [3H]SCH 58261 (A2A), 125I-AB-MECA (A3).

u

Bridges et al., 1988; brain (A1), striatum (A2A); radioligand [3H]CHA (A1), [3H]NECA (A2A); DPMA or PD 125944 is compound 16 in this paper.

v

Trivedi et al., 1989; brain (A1), striatum (A2A); radioligand [3H]CHA (A1), [3H]NECA (A2A).

w

Jacobson et al., 1987; brain (A1), radioligand [3H]PIA (A1).