CMT affected the action potential and contraction of guinea pig atrial muscles by antaganizing histamine H 2 receptor and reducing activities of Na + ,K + and Ca 2+ channels.

• CMT对豚鼠右心房肌有明显抑制作用，其机制可能是通过H2受体，阻断Na＋、K＋、Ca2＋通道所实现的。