大鼠三叉神经半月神经节内一氧化氮合酶阳性神经元的分布、投射及其与CGRP、SP的关系

PROJECTION OF NADPH-DIAPRORASE-CONTAINING NEURONS IN SEMILUNAR GANGLION OF THE RAT WITH REFERENCE TO ITS COEXISTENCE WITH CALCITONIN GENE-RELATED PEPTIDE AND SUBSTANCE P

用还原型尼克酰胺腺嘌呤二核苷酸脱氢酶组织化学方法观察了大鼠三叉神经半月神经节内一氧化氮合酶阳性神经元的分布．结果发现约５～８％的节细胞呈一氧化氮合酶阳性，几乎均是中、小细胞，弥散地分布在神经节各处．结合荧光金逆行追踪技术观察，发现荧光金注入三叉神经脊束核尾侧亚核浅层后，约９０％的一氧化氮合酶阳性节细胞被逆行标记，提示半月神经节内的一氧化氮合酶阳性神经元主要投射于三叉神经脊束核尾侧亚核浅层．用一氧化氮合酶组织化学反应结合荧光金逆行追踪技术及ＣＧＲＰ、ＳＰ免疫荧光技术进行重合处理的结果显示，在向三叉神经脊束核尾侧亚核投射的一氧化氮合酶阳性半月节神经元中，约６０％呈ＣＧＲＰ样免疫阳性，约６５％呈ＳＰ样免疫阳性．结合文献及本文结果，可以认为半月神经节向三叉神经脊束核尾侧亚核浅层投射的一氧化氮合酶与ＣＧＲＰ或ＳＰ共存的神经元可能在面口部伤害性信息的传递和调控中起重要作用．

The presence of reduced nicotinamide adenine dinucleotide phosphate (NADPH ) -diaphorase activity was stud led histochemically in the semilunar ganglion of the rat, Only 5～8% of the total ganglionic cells exhibited positive reaction. Positive cells were sparsely scattered throughout the ganglion, and alment all of them were small to medium in size. The result of combined histochemistry of NADPH-diaphorase and retrograde fiber tracing with fluorogold revealed that 90% of nitric oxide synthase positive ganglionic neurons projected to the superficial lamina of nucleus caudalis of the spinal trigeminal nucleus (Vc). It indicates that the nitric oxide synthase positive neurons in semilunar ganglias are one of the main source of the nitric oxide synthase positive fibers and terminals in superficial laminae of Vc.Results of histochemistry of NADPH-d combined with fluorogold retrograde fiber tracing and calcitonin gene-related peptide or substance P fluorescent immunohistochemistry revealed that,nitric oxide synthase colocalized with calcitoningene-related peptide and substance P in 60 % and 65 %, respectively, of the nitric oxide syntbase-staining ganglionic cells which project to the superficial llaminae of Vc. These cells were small to medium in size. It is well known that the spinal trigeminal nucleus is involved in the transmission and modulation of the oro-facial sensory information, and the nucleus caudalis of the spinal trigeminal nucleus is primarily responsible for relaying oro-facial nonreflexive nociceptive information. Collectively, these data suggest that the semilunar ganglionic cells, which contain nitric oxide synthase and calcitonin gene-related peptide or substance P and project to superficial laminae of Vc,might play an important role in oro-facial nociceptive processing via nitric oxide production.