Pezalla P D, Dicig M
Brain Res. 1984 Apr 2;296(2):356-60. doi: 10.1016/0006-8993(84)90073-8.
Immobilization of frogs for 1 h induces analgesia which is blocked but not reversed by low doses of naloxone. After 9 days of daily immobilization for 1 h, the treatment fails to cause analgesia thus indicating that tolerance has developed. Animals tolerant to immobilization-induced analgesia do not show cross-tolerance to the analgesic action of morphine. The development of tolerance to this form of stress-induced analgesia and the ability of naloxone to prevent its occurrence indicate the involvement of opioid pathways. The lack of cross tolerance to morphine suggests that mu receptors are not involved.
将青蛙固定1小时可诱导产生镇痛作用，低剂量纳洛酮可阻断但不能逆转这种镇痛作用。在每天固定1小时，持续9天后，该处理未能引起镇痛，这表明已经产生了耐受性。对固定诱导的镇痛产生耐受性的动物对吗啡的镇痛作用没有交叉耐受性。对这种形式的应激诱导镇痛产生耐受性以及纳洛酮预防其发生的能力表明阿片类途径参与其中。对吗啡缺乏交叉耐受性表明μ受体未参与。
