Table 1.
Threshold concentration of agonist inducing a relaxant response, maximum relaxation (relaxant responses to all agonists were expressed as % inhibition of the AVP-induced contraction) observed at 1 mM concentration, and p[A]25 (concentration that induced 25% relaxation) values±s.e.m. of six to eight experiments in the hamster proximal urethra
| Threshold concentration (μM) | Relaxation in response to 1 mM (%) | p[A]25 | |
|---|---|---|---|
| ATP | 1.0 | 74.9±0.2 | 4.13±0.07 |
| ADP | 1.0 | 70.0±4.8 | 4.03±0.07 |
| Adenosine | 1.0 | 68.6±3.0 | 4.28±0.05 |
| α,β-meATP | 0.3 | 53.8±3.6 | 3.50±0.08a,b |
| β,γ-meATP | 0.1 | 63.7±4.4 | 4.25±0.09 |
| 2-MeSADP | 0.1 | 73.1±4.9 | 4.45±0.10 |
| 2-MeSATP | 3.0 | 59.0±3.1 | 3.89±0.07a,b |
| CTP | 100 | 44.4±3.3 | 3.31±0.17a,b |
| GTP | 30 | 32.0±5.5 | 3.16±0.16a,b |
| TTP | 10 | 48.1±3.9 | 3.43±0.12a,b |
| UDP | 3.0 | 19.2±4.5 | <3.00 |
| UTP | 1.0 | 34.0±3.8 | 3.23±0.13a,b |
a
Indicates significant difference of agonist p[A]25 values from p[A]25 of ATP (P<0.05 or less).
b
Indicates significant difference of agonist p[A]25 values from p[A]25 of 2-MeSADP (P<0.05 or less).