Yitzhaky J, Frenk H, Urca G
Brain Res. 1982 Apr 8;237(1):193-201. doi: 10.1016/0006-8993(82)90567-4.
Repeated stimulation of the amygdaloid complex in rats results in the kindling of epileptic seizures. During the process of kindling and prior to the appearance of full behavioral convulsions, naloxone-sensitive changes in responsiveness to noxious stimulation occur, which disappear with repeated stimulation. When full behavioral convulsions appear, a short period of post-ictal behavioral depression (PID) can be seen immediately following convulsions. Naloxone either attenuates or completely blocks the occurrence of the PID. In order to test further the opioid nature of these phenomena, the development of tolerance to PD with repeated stimulation and the development of cross-tolerance to the analgesic and motor depressant effects of morphine were tested in kindled animals. Repeated elicitation of full behavioral convulsions resulted in a progressive decrease of PID duration across days. PID was also decreased in morphine tolerant animals. Repeated convulsions also induced cross-tolerance with both morphine analgesia and morphine-induced catalepsy. In contrast, animals tested following 10 days of amygdaloid stimulation which did not cause full behavioral convulsions to develop, showed cross-tolerance to the analgesic but not the motor depressant effect of morphine. The possibility that two different opioid systems, which are independent of one another are activated during different phases of kindling is discussed.
反复刺激大鼠杏仁核复合体可导致癫痫发作的点燃效应。在点燃过程中以及完全行为性惊厥出现之前，对有害刺激的反应性会发生纳洛酮敏感的变化，这种变化会随着反复刺激而消失。当出现完全行为性惊厥时，惊厥后会立即出现一段短暂的发作后行为抑制（PID）。纳洛酮可减轻或完全阻断PID的发生。为了进一步测试这些现象的阿片样物质性质，在点燃动物中测试了反复刺激后对PID的耐受性发展以及对吗啡镇痛和运动抑制作用的交叉耐受性发展。反复引发完全行为性惊厥导致PID持续时间随天数逐渐减少。吗啡耐受的动物中PID也有所减少。反复惊厥还诱导了对吗啡镇痛和吗啡诱导的僵住症的交叉耐受性。相比之下，在接受10天杏仁核刺激但未引发完全行为性惊厥的动物中进行测试，结果显示对吗啡的镇痛作用有交叉耐受性，但对运动抑制作用没有交叉耐受性。本文讨论了在点燃的不同阶段激活两个相互独立的不同阿片样物质系统的可能性。
