蝎毒中枢镇痛机制的初步探讨

目的：研究BmK蝎毒是能过何种受体实现其中枢镇痛作用的;外侧隔核是否是BmK蝎毒产生中枢镇痛作用的重要部位之一。方法：用辐射热一甩尾法测定痛阈,用玻璃微电极记录束旁核的单位放电;通过不锈钢套管向侧脑室和外侧隔核内微量注射0.01％BmK蝎毒。结果：向大鼠侧脑室2μl0.01%蝎毒可明显升高痛阂。该效应可被侧脑室注射2μl0.25%纳洛酮完全翻转,向隔核内注射0.5μl0.01%BmK蝎毒,分别对束帝核中的71％（15／21）痛兴奋单位和83％（5／6）痛抑制单位对痛刺激的反应减北,而对痛无关单位的电活动夫明显影响。结论：BmK蝎毒的中枢镇痛作用可能主要是通过吗啡受体实现的;隔核是BmK蝎毒产生中枢镇痛作用的重要部位之一。

Preliminary study of analgesic mechanism of Buthus martensii Karsch (BmK) venom on central nervous system

To investigate whether or not the lateral septal nucleus(LS) was one of important analgesic areas of Bmk venom in the central nervous system (CNS), and , targeting on which receptor,analgesic effect was produced by i t. Methods: Pain threshold of skin was observed by the latent perio d of tail flick evoked by radiant heat. Glass micropipette placed in Pf was u sed to record unit dischanges of neurons in it, before and after 0.01% BmK venom were injected into LS. Stainless steel cannula placed in the lateral cerebral v entricle (icv) and LS was used for microinjection.Results: After inj ection of 2 μl 0.01% BmK venom into icv of rat,the pain threshold was aparen tly raised, which was completety returned by injection of 0.5 μl 0.25% naloxo ne into icv. After 0.5 μl 0.01% Bmk venom was injected into LS, 71%(15/21)nocic eptive-on neurons and 83.3%(5/6) nociceptive-off neurons decreased the nocicep tive response to tail pinch, but no evident effect was observed in the non-noci ceptive neurons. Conclusion:The analgesic effect of BmK venom was pr obably realized mainly by the opiate receptor, and LS was one of important analg esic areas of BmK venom on CNS.