阻断大鼠杏仁中央核AMPA受体对臂旁核味觉反应的影响(英文)  

Blocking of AMPAreceptors in the central amygdaloid nucleus modulates the parabrachial nucleus taste responsesin rats

作　　者：康怡[1] 闫剑群[1] 黄涛[1] 

机构地区：[1]西安交通大学医学院生理教研室,西安交通大学环境与疾病相关基因教育部重点实验室,西安710061

出　　处：《生理学报》2004年第6期671-677,共7页Acta Physiologica Sinica

基　　金：This work was supported by the National Natural Science Foundation of China (No. 30270454; 30300111)

摘　　要：以往的研究表明,电刺激或损毁杏仁中央核明显改变臂旁核味觉神经元的活动。为了研究杏仁中央核内的兴奋性受体是否参与此调节,本实验应用细胞外记录方法,在乌拉坦麻醉的大鼠观察了杏仁中央核内微量注射6-氰基-7-硝基喹喔啉-2,3- 二酮(CNQX)前后臂旁核味觉神经元对四种基本味觉刺激反应的变化。结果表明,杏仁中央核内注射 CNQX 对 30% 的臂旁核神经元产生时间依赖性的抑制作用,此抑制作用以对盐酸和盐酸奎宁刺激引起的反应尤为明显(P<0.05)。根据对味觉刺激的优势反应,40% 的NaCl优势、30% 的HCl优势和20% 的奎宁优势反应神经元在注射CNQX 后对至少一种味觉刺激的反应降低;盐酸优势和奎宁优势反应神经元对各自的优势反应在杏仁中央核内注药后均明显降低(P<0.01)。相关性分析表明,在注射 CNQX 后,臂旁核味觉神经元对 NaCl 和其它三种味觉刺激物之间的分辨能力降低。以上结果表明,杏仁中央核内的AMPA 受体可能参与杏仁核对臂旁核味觉神经元的下行调控。Taste responses in the parabrachial nucleus (PBN) are significantly affected by stimulation or lesion of the central nucleus of the amygdala (CeA). To examine if the glutamate receptors in the CeAare involved in this modulation, the effects of microinjection of 6-cyano-7- nitro-quinoxaline-2, 3-dione (CNQX), an AMPA receptor antagonist, into the CeAon the activities of PBN taste neurons were observed by using extracellular recording technique. Responses of PBN taste neurons to taste stimuli were observed before and after CNQX administered to the CeA. In general, drug administration produced a time-dependent suppress of the responses in 30% PBN taste neurons, with the firing rates to HCl and QHCl were significantly lowered (P<0.05). According to the best-stimulus category, 40% NaCl-best (6/15), 30% HCl-best (3/10) and 20% QHCl-best (1/5) neurons decreased their responses to at least one basic taste stimulus after CNQX injection. In HCl- and QHCl-best neruons, the main responses were significantly inhibited after drug injections (P<0.01). The correlation coefficient of responses between the NaCl and the other three tastants decreased after drug administration to the CeA. These results suggest that AMPA receptors within the CeA may be involved in the descending modulation in the PBN taste neurons.

关 键 词：臂旁核 杏仁中央核 味觉 微量注射 6-氰基-7-硝基喹喔啉-2 3-二酮 

分 类 号：Q434[生物学—生理学]