[Effects of petroleum ether extract of Peucedanum praeruptorum Dunn on rabbit trachea smooth muscles].

The contractions of isolated rabbit trachea smooth muscles by acetylcholine and potassium chloride were attenuated by petroleum ether extract of Peucedanum praeruptorum pretreatment. The dose-effect curve of acetylcholine was shifted to the right, and the maximal response was diminished. The effect was non-competitive and dose-dependent.