Methods: We used ethanol at different concentrations for the sciatic nerve stem of the unorganized hoptoad and measures its absolute refractory period.

方法：本实验对离体蟾蜍坐骨神经干进行不同浓度乙醇处理，测其绝对不应期。

Methods: By recording the action potential of sciatic trunk and contract curve of sural muscle of hoptoad, and checking the time of fatigue in nerve center, neuro-muscular junction and muscle.

方法：记录蟾蜍坐骨神经干动作电位和腓肠肌收缩曲线，测定低位运动中枢、神经-肌接头和骨骼肌出现疲劳的时间并加以比较。

Methods: By recording the action potential of sciatic trunk and contract curve of sural muscle of hoptoad, and measuring the time of fatigue in nerve centre, neuro-muscular junction and muscle.

方法：记录蟾蜍坐骨神经干动作电位和腓肠肌收缩曲线，测定低位运动中枢、神经肌接头、骨骼肌出现疲劳的时间并加以比较。

Methods: the action potential of sciatic trunk and contract curve of sural muscle of hoptoad were recorded, and the time of fatigue in nerve center, neuro-muscular junction and muscle was checked.

方法记录蟾蜍坐骨神经干动作电位和腓肠肌收缩曲线，测定低位运动中枢、神经-肌肉接头和骨骼肌出现疲劳的时间并加以比较。