Drug | ED50 | Dose Ratio (Bradycardia/ Bronchoconstriction) | |
---|---|---|---|
Bronchoconstriction | Bradycardia | ||
mg/kg i.v. | |||
Compound A | 0.022 | ≥10 | ≥450 |
(0.015–0.030) | |||
Darifenacin | 0.017 | 0.18 | 11 |
(0.013–0.021) | (0.12–0.26) |
Drugs were administered intravenously 5 min before i.v. injection of acetylcholine. The ED50 values were calculated from dose-response curves with least-squares linear regression analysis from the percentage of inhibition of bronchoconstriction (acetylcholine-induced increases in RL) or bradycardia (acetylcholine-induced decreases in heart rate) versus the log molar doses of the drugs. The values in parentheses indicate the 95% confidence limits.