丘脑网状核在大鼠睡眠-觉醒周期中的调节作用

目的 观察丘脑网状核(Rt)对大鼠睡眠-觉醒周期的影响.方法 采用脑立体定位技术确定Sprague-Dawley大鼠双侧Rt插管位置并进行核团埋管,同时安装脑电和肌电电极用于记录大鼠皮层脑电活动和肌电活动.运用多导睡眠描记技术观察Rt内微量注射药物后大鼠睡眠-觉醒指标变化情况.结果 Rt内微量注射L-谷氨酸(L-Glu)后与对照组比较觉醒时间增加 分别为(53.3±4.9)%,(40.9±5.3)%,P <0.01],睡眠时间减少 分别为 (46.7±4.9) %,(59.1±5.3)%,P <0.01];而微量注射γ-氨基丁酸 (GABA),环磷酸腺苷 (cAMP) 引起睡眠时间分别增加 14.0 %( t = 3.136, P <0.01) 和 12.2 % ( t =3.187,P <0.01),觉醒时间分别减少20.3 % ( t = 3.136,P <0.01) 和 21.7% ( t = 3.003,P <0.01).Rt内微量注射吗啡引起觉醒时间增加 分别为(43.2±7.7)%,(32.6±6.1)%,P <0.01 ],睡眠时间减少 分别为 (56.8±7.7)%,(67.4±6.1)%,P <0.01],而微量注射阿片受体阻断剂纳络酮可阻断吗啡的促觉醒作用 ( t =2.538,P <0.05). 结论 Rt参与大鼠睡眠-觉醒周期的调节,兴奋Rt可促进觉醒,抑制Rt 可促进睡眠;并且Rt可能是阿片类物质参与睡眠调节的中枢靶区之一.

Effect of nucleus reticularis thalami on sleep-wakefulness cycle of rat

Objective To observe effect of nucleus reticularis thalami (Rt) on sleep-wakefulness cycle of rat.Methods Two stainless steel cannulae were implanted into Sprague-Dawley rats'bilateral Rt by using brain stereotaxic technique. At the same time,four copper electrodes were screwed into the skull for electroencephalogram (EEG) recoding and two silver wires in the neck muscle for electromyogram (EMG) recording. After drugs were microinjected into Rt,sleep-wakefulness cycle was observed by polysomnography. Results Wakefulness was enhanced (53.3±4.9) %,(40.9±5.3) %,P <0.01] and sleep was reduced(46.7±4.9) %,(59.1±5.3) %,P <0.01] after L-glutamate (L-Glu) was microinjected into Rt,while microinjection of γ-amino-butyric acid (GABA) and 3'-5'-cyclic adenosine monophosphate (cAMP) into Rt led to the opposite effects:sleep was increased by 14.0 % ( t = 3.136, P <0.01) ,12.2 % ( t = 3.187,P <0.01) and wakeful-ness was decreased by 20.3 % ( t = 3.136,P <0.01) ,21.7 % ( t = 3.003,P <0.01). Microinjection of morphine into Rt can enhance wakefulness(43.2±7.7) %,(32.6±6.1) %,P <0.01 ] and reduce sleep (56.8±7.7) %,(67.4±6.1) %,P <0.01],whereas microinjection of naloxone,an opioid receptor antagonist,into Rt,abolished the effect of morphine completely ( t = 2.538,P <0.05). Conclusion Rt plays an important role in regulating sleep and wakefulness. Excitement of Rt promotes wakefulness,while,inhibition of Rt causes sleep. Rt may be one of the sleep-regulatory sites of opioid-like substances.