大鼠囊泡膜谷氨酸转运体样和谷氨酸脱羧酶样阳性终末与表达GABAA受体α3亚单位的三叉神经中脑核神经元之间的联系

目的 观察大鼠三叉神经中脑核(Vme)内囊泡膜谷氨酸转运体(VGluT1和DNPI)样和谷氨酸脱羧酶(GAD)样阳性终末与GABAA受体α3亚单位(GABAARα3)样阳性神经元之间的联系。方法 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。结果 在Vme吻尾方向上，有大量的神经元胞体呈GABAARα3样免疫阳性，这些神经元多为大的假单极神经元(直径为25—50μm)。VGluT1样、DNPI样和GAD样免疫阳性终末密集分布于Vme内，一些VGluT1／DNPI样和GAD样阳性终末包绕在GABAARα3样阳性Vme神经元胞体周围，并与之形成密切接触。结论 Vme神经元在介导口面部本体感觉信息的传递过程中，可能同时接受中枢其他来源的谷氨酸能和GABA能终末的调控，其中GABA能终末的作用可能是通过GABAA受体实现的。

CONNECTIONS BETWEEN VESICULAR GLUTAMATE TRANSPORTERS-,GAD-LIKE IMMUNOREACTIVE TERMINALS AND GABAA RECEPTOR α3 SUBUNIT-LIKE POSITIVE NEURONS IN MESENCEPHALIC TRIGEMINAL NUCLEUS OF THE RAT

Objective To observe the association of vesicular glutamate transporter of type Ⅰ(VGluT1)-like immunoreactive(LI),the differentiation-associated Na+-dependent inorganic phosphate cotransporter(DNPI)-LI and glutamic acid decarboxylase(GAD)-LI terminals with GABAA receptor α3 subunit(GABAARα3)-LI neurons in mesencephalic trigeminal nucleus of the rat. Methods Triple-immunofluorescence histochemical staining technique and confocal laser-scanning microscopy were used. Results A large number of neuronal cell bodies showed GABAA Rα3-LI immunoreactivity at all rostrocaudal levels of the Vme,and most of GABAARα3-LI cells were large (25-50μm) pseudounipolar neurons.The dense VGluT1-LI,DNPL-LI and GAD-LI terminals distributed widely in Vme,some VGluT1/DNPI-LI and GAD-LI terminals surrounded the somata of the GABAARα3-LI Vme neurons,and made close contacts with them.Conclusion Proprioceptive sensory signals from the orofacial region might be modulated at the level of the primary afferent cell bodies in the Vme both by glutamatergic- and GABAergic-axonal terminals from other brain areas,and the effect of GABAergic-terminals might be mediated by post-synaptical GABAA receptors.