Table 2.
Effects of blockers of P2, P2Y1and P1 purinoceptors on relaxations evoked by ATP, and of blockers of P1, P2Y1, P2Y12 and P2Y13receptors on responses induced by ADP
|
ATP |
|||
|---|---|---|---|
| n | pEC50 | R (%) | |
| Control | 8 | 3.7 ± 0.1 | 98.1 ± 1.4 |
| Suramin (100 µM) | 8 | 3.4 ± 0.1* | 97.9 ± 2.9 |
| Control | 7 | 3.9 ± 0.1 | 79.7 ± 3.0 |
| PPADS (30 µM) | 7 | 3.8 ± 0.2 | 78.8 ± 5.8 |
| Control | 7 | 3.7 ± 0.1 | 95.5 ± 3.7 |
| MRS2179 (10 µM) | 7 | – | 80.0 ± 5.1* |
| Control | 7 | 4.1 ± 0.1 | 92.9 ± 4.7 |
| 8-SPT (100 µM) | 7 | 3.8 ± 0.1* | 77.1 ± 6.5 |
| Control | 6 | 4.1 ± 0.1 | 92.1 ± 4.5 |
| MRS2179 + 8-SPT | 6 | 3.7 ± 0.1* | 85.5 ± 9.1 |
| ADP | |||
| Control | 9 | 4.1 ± 0.1 | 87.9 ± 4.0 |
| 8-SPT (100 µM) | 9 | 4.0 ± 0.2 | 88.1 ± 3.5 |
| Control | 6 | 4.1 ± 0.1 | 94.9 ± 4.3 |
| PPADS (30 µM) | 6 | – | 78.0 ± 7.0* |
| Control | 7 | 4.0 ± 0.1 | 97.9 ± 2.0 |
| MRS2179 (10 µM) | 7 | – | 75.1 ± 9.7* |
| Control | 6 | 4.2 ± 0.1 | 92.0 ± 6.1 |
| Clopidogrel (10 µM) | 6 | 4.2 ± 0.1 | 88.7 ± 5.0 |
| Control | 7 | 4.0 ± 0.1 | 89.7 ± 5.5 |
| MRS2211 (10 µM) | 7 | 3.9 ± 0.1 | 91.0 ± 5.1 |
Results are expressed as mean ± SEM of n experiments.
P < 0.05 versus control (paired t-test).
8-SPT, 8-(p-sulphophenyl)theophylline; ADP, adenosine 5′-diphosphate; ATP, adenosine 5′-triphosphate; MRS2179, 2′-deoxy-N6-methyladenosine 3′,5′-bisphosphate tetrasodium; MRS2211, 2-[(2-chloro-5-nitrophenyl)azo]-5-hydroxy-6-methyl-3-[(phosphonooxy)methyl]-4-pyridine carboxaldehyde; pEC50 = −log EC50, where EC50 is the concentration of agonist producing 50% relaxation of phenylephrine (PhE)-induced contraction; PPADS, pyridoxal phosphate-6-azo(benzene-2,4-disulphonic acid); R is the relaxation, expressed as a percentage of the PhE-induced contraction, evoked at the highest concentration of agonist used: ATP, 1 mM; and ADP, 1 mM.