GABA的镇痛、催眠、遗忘作用及其与GABA_A受体的关系

Relationship between GABAA receptor and the analgesic、hypnotic and amnesic effects induced by GABA

目的探讨脑内GABA的镇痛、催眠、遗忘作用及其与GABAA受体的关系。方法小鼠侧脑室注射(intracerebrov-entricular,icv)GABA或icvGABA后,静脉注射(intravenous,iv)GABAA受体阻断药一叶秋碱(securinine,Se),分别用热板和扭体实验、催醒实验、跳台和避暗实验,观察小鼠热板疼痛指数(pain threshold index in hot-plate test,HPPI)和扭体次数(writhing times)、睡眠时间(sleeping time,ST)、跳台和避暗的潜伏期(latancy)和错误次数(number of errors)的变化。结果GABA能剂量依赖性地增大HPPI,减少扭体次数;延长ST;缩短跳台和避暗潜伏期,增加错误次数;Se能拮抗以上作用。结论GABA可产生镇痛、催眠和遗忘效应,GABAA受体是GABA上述作用的重要靶位。

Aim To investigate the effect of the GABAA receptor on the analgesia, hypnosis and amnesia induced by GABA in mice. Methods GABA was intracerebroventricularly （icv） injected and securi- nine, a GABAA receptor antagonist, was intravenously （iv） injected after the GABA intracerebroventricularly injection. Then four techniques including hot-plate test, acetic acid-induced writhing test, awaken test as well as step-through test ＆ step-down test were employed to evaluate the effects on the pain index in hot- plate test（ HPPI）, the writhing times, the sleeping time （ST） and the latency ＆ the number of errors. Results GABA increased the HPPI and ST, but decreased writhing times and the latency ＆ increased the number of errors in conscious mice;the above effects are dosedependent. Securinine could antagonize the effects stimulated by GABA. Conclusion GABA lead to analgesia, hypnosis and amnesia. GABAA receptor might be the important target for these effects.