Table 3.
Potency of Selected Agonists and Antagonists at P2X Receptors Expressed as EC50 or IC50 Values in nM in Functional Assays (in Human or Rat)a,b
| P2X1 | P2X2 | P2X3 | P2X4 | P2X5 | P2X6 | P2X7 | |
|---|---|---|---|---|---|---|---|
|
| |||||||
| Agonists | |||||||
| 1, ATP | 56 | 1400 | 340 | 500, 1000 | 1000 | 1000 | 780,000 |
| 2, ADP | 10,000 | >100,000 | >100,000 | 28,000 b | 18,300 | 11,000 | |
| 7, ATPγS | 2300 | 1500 | 690 | 2300 | 600 | 1300 | |
| 8, ADPβS | 2500 | 100,000 | 8800 | 25,000 | |||
| 10, α,β–meATP | 200 | 100,000 | 740 | 33,000 | >7000 | >8000 | >100,000 |
| 11, β,γ–meATP | 2000 | 9200 | |||||
| 13, 2-MeSATP | 54 | 1500 | 350 | 7400, 1000 | 1000 | 600 | |
| 15, HT-AMP | 840 b | 180,000 | 350 b | 20,000 b | |||
| 16, PAPET-ATP | 98 | 10,000 | 17 | 15,000 b | |||
| 19, Bz-ATP | 2 | 5,500 | 80 | 490 | 40,000 | 25,000 | 52,000 |
| 59, Ap4A | 182 | 15,000 | 500 | 1000 c | |||
| Antagonists | |||||||
| 23, suramin | 1000 | 10,400 | 3000, 14,900 | >100,000 | 4000 | >100,000 | 92,000 |
| 25, NF023 | 210 | >50,000 | 28,500 | >100,000 | |||
| 27, Reactive blue 2 | 360 | 128,000 | |||||
| Pyridoxal-5-phosphate | 3000 | 39,500 | 219,000 | ||||
| 36, PPADS | 99 | 1200 e | 240, 1700 | 10,000, >100,000 | 2600 | >100,000 | 62,000 |
| 37, isoPPADS | 43 | 400 | 84 | ||||
| 40, PPNDS | 14 | ||||||
| 47, TNP-ATPh | 6 | 2000 | 0.9 | 15,200 | |||
| 50, MRS 2179 | 1150 | >10,000 | 13,000 | >10,000 | >30,000 | ||
| 54a, KN-62 | >100,000 | 34 | |||||
| 65, lp5l | 1.5 | >30,000 | 2800 | potentiator | |||
| 72, MRS 2220 | 10,200 | >100,000 | 58,300 | >100,000 | |||
a
Effects of antagonists on inward current induced by activation by ATP, at the indicated concentrations, of recombinant rat P2X1 (1 μM), P2X2 (10 μM), P2X3 (3 μM), and P2X4 (30 μM) receptors, expressed in Xenopus oocytes, using the twin electrode voltage clamping technique, unless otherwise noted (methods in refs 431 and 438).
b
Rat (red), human (blue).
c
Partial agonist.