Results:When isoprenaline was injected a relaxation curve could be recorded; while acetylcholine was injected,a contraction curve could be recor ded.

• 结果：当注入舒张药异丙肾上腺素时，能记录到舒张曲线；当注入收缩药乙酰胆碱时，能记录到收缩曲线。