Lewis J W, Cannon J T, Liebeskind J C
Science. 1980 May 9;208(4444):623-5. doi: 10.1126/science.7367889.
Inescapable foot shock in rats caused profound analgesia that was antagonized by naloxone or dexamethasone when shock was delivered intermittently for 30 minutes, but not when it was delivered continuously for 3 minutes. Thus, depending only on its temporal characteristics, foot-shock stress appears to activate opioid or nonopioid analgesia mechanisms. Certain forms of stress may act as natural inputs to an endogenous opiate analgesia system.
对大鼠施加不可逃避的足部电击会引发深度镇痛。当间歇性电击30分钟时，这种镇痛作用会被纳洛酮或地塞米松拮抗，但当持续电击3分钟时则不会。因此，仅根据其时间特征，足部电击应激似乎会激活阿片类或非阿片类镇痛机制。某些形式的应激可能作为内源性阿片镇痛系统的天然输入信号。
