Table 4.
Effects of blockers of A1, A2A, A2B and A3purinoceptors on relaxations evoked by adenosine and NECA
|
Adenosine |
NECA |
|||||
|---|---|---|---|---|---|---|
| n | pEC50 | R (%) | n | pEC50 | R (%) | |
| Control | 6 | 3.9 ± 0.1 | 100 ± 0 | 6 | 7.2 ± 0.1 | 92.0 ± 4.9 |
| DPCPX (10 µM) | 6 | 3.8 ± 0.1 | 97.1 ± 2.3 | 6 | 7.3 ± 0.1 | 85.1 ± 7.7 |
| Control | 7 | 4.2 ± 0.1 | 100 ± 0 | 8 | 7.4 ± 0.1 | 95.3 ± 4.7 |
| ZM241385 (0.1 µM) | 7 | 3.9 ± 0.1* | 98.5 ± 5.7 | 8 | 6.9 ± 0.1* | 94.1 ± 4.3 |
| Control | 6 | 4.0 ± 0.1 | 84.8 ± 9.7 | 6 | 7.4 ± 0.1 | 93.9 ± 4.0 |
| PSB1115 (0.1 µM) | 6 | 4.0 ± 0.1 | 82.6 ± 6.3 | 6 | 7.4 ± 0.1 | 89.9 ± 7.1 |
| Control | 6 | 4.0 ± 0.1 | 100 ± 0 | 6 | 7.1 ± 0.1 | 92.0 ± 5.8 |
| MRS1220 (10 µM) | 6 | 4.0 ± 0.1 | 100 ± 0 | 6 | 7.1 ± 0.1 | 93.2 ± 5.0 |
Results are expressed as mean ± SEM of n experiments.
P < 0.05 versus control (paired t-test).
DPCPX, 8-cyclopentyl-1,3-dipropylxanthine; MRS1220, N-[9-chloro-2-(2-furanyl)[1,2,4]-triazolo[1,5-c]quinazolin-5-yl]benzene acetamide; NECA, 5′-N-ethylcarboxamidoadenosine; pEC50 = −log EC50, where EC50 is the concentration of agonist producing 50% relaxation of phenylephrine (PhE)-induced contraction; PSB1115, 4-(2,3,6,7-tetrahydro-2,6-dioxo-1-propyl-1H-purin-8-yl)-benzenesulphonic acid potassium salt; R is the relaxation, expressed as a percentage of the PhE-induced contraction, evoked at the highest concentration of agonist used: adenosine, 1 mM; and NECA, 1 µM; ZM241385, 4-(-[7-amino-2-(2-furyl)[1,2,4]triazolo[2,3-a][1,3,5]triazin-5-ylamino]ethyl) phenol.