The autonomic nervous system uses the hormone adrenaline, a neurotransmitter, or chemical messenger, to send signals to various parts of the body to activate the fight-or-flight response.

• 自身的神经系统利用肾上腺素，一种神经传递介质或者说是化学信使，把信号传递在身体的各个部位以刺激“战或逃反映”。