【摘要】 清醒箭毒化雄性大鼠在人工呼吸维持下,观察电针对中缝大核(NRM)的效应。实验显示电针可使 NRM 单个神经元放电增加。且此效应可被静脉注射纳洛酮完全阻断,表明它是通过内源性鸦片样物质(OLS)作用于鸦片受体而实现的。进一步电刺激 OLS 二系统中与镇痛有关的核团:下丘脑室周核(HPV:富有脑啡肽能神经元的部位)和弓状核(AR:β-内啡肽能神经元集中之处),发现分别电刺激单侧 HPV 和 AR 对 NRM 神经元亦起兴奋作用,与电针效应的幅度、形式和时程基本一致。静脉注射纳洛酮不仅能阻断电针对 NRM 的效应,且使 NRM 神经元自发放电率降低,说明“正常情况下”脑内 OLS 系统即对 NRM 具有紧张性激活作用。更多还原

【Abstract】 Experiments were undertaken to examine the effects of electro-acupuncture(EA)and/or,stimulation of the nucleus periventricularis hypothalami(HPV:oneof nuclei of the enkephalin system)or the nucleus arcuatus hypothalami(AR:the origin of β-endorphin system)on nucleus raphe magnus(NRM)in conscious,paralysed male rats.The unit discharge rate of NRM neurones was increased byEA.Naloxone(i.v.)blocked this effect completely.Stimulation of unilateralHPV or AR activated NRM neurons in the same way as the effect of EA,andso did EA combined with stimulation of HPV or AR.These results suggested thatthe mechanisms of the excitatory effects of EA and HPV-or AR-stimulation onNRM might be similar.Naloxone(i.v.)not only blocked the effect of EA onNRM,but also decreased the spontaneous discharge rate of NRM nuerons,implying that the brain endogenous opiate system has a tonic excitatory effect onNKM under“normal condition”.更多还原