大鼠三叉神经中脑核内囊泡膜谷氨酸转运体样和GAD样阳性末梢与GABA_A受体α1亚单位样阳性神经元的联系  

Association of vesicular glutamate transporters- and GAD- like immunore-active terminals with GABA_ A- receptor α1 subunit-like positive neurons in the mesencephalic trigeminal nucleus of the rat

作　　者：李金莲[1] 陈鹏[1] 熊抗辉[1] 

机构地区：[1]第四军医大学基础部解剖学教研室暨梁銶琚脑研究中心

出　　处：《中国神经科学杂志》2002年第2期477-481,共5页

基　　金：国家自然科学基金资助项目 ( 39870 2 62 ) ;国家教育部高等学校骨干教师资助计划资助

摘　　要：最近已在哺乳类动物脑内克隆出两种新的脑内特殊的Na+依赖的无机磷酸转运体 ,它们均属于囊泡膜谷氨酸转运体 ,被分别命名为VGluT1(Vesicularglutamatetransporteroftype1)和DNPI (differentiation associatedNa+ dependentinorganicphosphatecotransporter)。本研究应用免疫荧光组织化学三重染色技术 ,在激光共聚焦显微镜下观察了大鼠三叉神经中脑核 (Vme)内VGluT1样和DNPI样以及谷氨酸脱羧酶 (GAD)样阳性末梢与GABAA受体α1亚单位 (GABAARα1)样阳性神经元之间的联系。结果显示 :①几乎所有的Vme神经元均呈GABAA受体α1亚单位样免疫阳性 ,吻尾方向在其全长出现 ,这些神经元绝大多数为大的假单极神经元 (直径为 2 5～ 5 0μm) ,但也有小部分为直径小于 2 5 μm的神经元。②大量的VGluT1样和DNPI样免疫阳性的神经纤维和末梢广泛分布于Vme内 ,其中DNPI样阳性纤维和末梢的分布密度高于VGluT1;同时还观察到GAD样阳性纤维和末梢也密集分布于Vme内。③VGluT1样、DNPI样和GAD样免疫阳性终扣分别包绕在GABAA受体α1亚单位样阳性Vme神经元胞体周围 ,并与之形成密切接触。以上结果提示 :Vme神经元在介导面口部本体感觉信息的传递中 ,可能同时接受中枢其他来源的谷氨酸能和GABA能末梢的调控 ,其中GABA能的投射末梢?Two kinds of novel brain specific Na + dependent inorganic phosphate cotransporter were cloned recently from the brain of vertebrate animal and were known as the vesicular glutamate transporters. They were named the vesicular glutamate transporter of type1 (VGluT1) and the differentiation associated Na + dependent inorganic phosphate cotransporter (DNPI), respectively.In the present study, the triple immunofluorescence histochemical staining techniques were used to observe the association of VGluT1 like immunoreactive ( LI), DNPI LI and the glutamic acid decarboxylase (GAD) LI terminals with GABA A receptor α1 subunit(GABA A Rα1) LI neurons in the mesencephalic trigeminal nucleus (Vme) of the rat under a confocal laser scanning microscopy. The results indicated: ①Almost all neuronal cell bodies through the whole rostrocaudal extent of Vme showed GABA A Rα1 LI and the vast majority of them were large pseudounipolar neurons(diameter 25～50 μm), though a few of neurons were small cells (diameter ≤25 μm).②A considerable number of VGluT1 LI, DNPI LI and GAD LI terminals and varicosities were widely distributed in Vme, and the density of distribution of DNPI like varicosities was higher than that of VGluT1 LI. ③Axonal varicosities with dense of VGluT1 LI or DNPI LI and GAD LI frequently surrounded the somata of Vme neuronal profiles showing GABA A Rα1 LI and formed the close contact with them, respectively. The present results suggested that Vme neurons,in the transmission of the proprioceptive sensory information from the orofacial regions, received the modulation both glutaminergic and GABAergic axonal terminals. GABAergic terminals projecting to Vme might exert inhibitory regulation and control effects through GABA A R localizated in somata of Vme neurons on the transmission of orofacial region proprioceptive sensory information.

关 键 词：谷氨酸 囊泡膜谷氨酸转运体 GABA GABAA受体 三叉神经中脑核 免疫荧光组织化学 大鼠 

分 类 号：R329[医药卫生—人体解剖和组织胚胎学]