刺激和损毁蓝斑核对网状巨细胞核神经元放电的影响

Effects of Stimulation and Lesion of LC on the Discharges of NGC Neurons

对水合氯醛浅麻醉的大鼠观察了电刺激或损毁蓝脏核(LC)对延髓网状巨细胞(NGC)神经元自发放电及伤害性反应的影响。结果如下:1)在143个NGC神经元中有63个伤害性神经元,12个会聚神经元,68个非伤害性神经元。在伤害性神经元中,伤害兴奋性的占2/3,伤害抑制性的占1/3。2)电刺激同侧及对侧LC可分别抑制64％及68％的伤害性神经元的伤害性反应,对大部分非伤害性神经元及会聚神经元无影响。3)损毁LC后,有45％(5/11个)伤害性神经元自发放电增加,67％(4/6个)伤害性神经元伤害性反应强度增加,且电刺激原LC位点的抑制作用减弱或消失。本工作说明,NGC伤害性神经元接受LC抑制性影响,对NGC及LC在抗伤害中的作用进行了讨论。

Effects of electrical stimulation and lesion of nucleus locus coeruleus ( LC ) on the spontaneous discharge of neurons in nucleus reticularis gigantocellularis ( NGC ) and their responses to noxious pinch stimulation were observed in light chloral hydrate anesthetized rats. The results were as follows.(1) In the 143 recorded units of NGC, there were 63 nociceptive neurons, 12 convergent neurons and 68 nonnociceptive neurons. Among the 63 nociceptive neurons,one third was nociception-inhibitory neurons and two thirds were nociception-excitatory neurons.(2) No discharges of most nonnociceptive and convergent neurons were influenced by LC stimulation. Either electrical stimulation of ipsilateral or contrala-teral LC inhibited nociceptive responses of 64% and 68% NGCnociceptive neurons respectively.(3) After LC lesion, spontaneous discharges of 45% (5/11) NGC neurons facilitated and nociceptive responses of 67% ( 4/6 ) NGC neurons increased too. The inhibition of LC stimulation on nociceptive responses disappeared when LC had been lesioned ,This work indicates that LC has inhibitory influences on some NGC nociceptive neurons.The role of NGC and LC in antinociception are discussed