Wang Q P, Nakai Y
Department of Neurobiology, Shanghai Medical University, China.
Brain Res Bull. 1994;34(6):575-85. doi: 10.1016/0361-9230(94)90143-0.
The dorsal raphe nucleus (DRN) is an important nucleus in pain modulation. It has abundant 5-HT neurons and many other neurotransmitter and/or neuromodulator containing neurons. Its vast fiber connections to other parts of the central nervous system provide a morphological basis for its pain modulating function. Its descending projections, via the nucleus raphe magnus or directly, modulate the responses caused by noxious stimulation of the spinal dorsal horn neurons. In ascending projections, it directly modulates the responses of pain sensitive neurons in the thalamus. It can also be involved in analgesia effects induced by the arcuate nucleus of the hypothalamus. Neurophysiologic and neuropharmacologic results suggest that 5-HT neurons and ENKergic neurons in the DRN are pain inhibitory, and GABA neurons are the opposite. The studies of the intrinsic synapses between ENKergic neurons, GABAergic neurons, and 5-HT neurons within the DRN throw light on their relations in pain modulation functions, and further explain their functions in pain mediation.
中缝背核（DRN）是疼痛调制中的一个重要核团。它有丰富的5-羟色胺（5-HT）神经元以及许多其他含有神经递质和/或神经调质的神经元。它与中枢神经系统其他部分广泛的纤维连接为其疼痛调制功能提供了形态学基础。其下行投射，通过中缝大核或直接投射，调制由脊髓背角神经元的伤害性刺激所引起的反应。在其上行投射中，它直接调制丘脑内痛觉敏感神经元的反应。它也可参与下丘脑弓状核诱导的镇痛效应。神经生理学和神经药理学结果表明，DRN中的5-HT神经元和脑啡肽能神经元具有疼痛抑制作用，而γ-氨基丁酸（GABA）能神经元则相反。对DRN内脑啡肽能神经元、GABA能神经元和5-HT神经元之间的内在突触的研究揭示了它们在疼痛调制功能中的关系，并进一步解释了它们在疼痛介导中的作用。
