阻断大鼠杏仁中央核AMPA受体对臂旁核味觉反应的影响
康怡, 闫剑群, 黄涛
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.陕西,西安 710061
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,该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({sl 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({sl P}<0.01)。相关性分析表明,在注射CNQX后,臂旁核味觉神经元对氯化钠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。
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
Blocking of AMPA receptors in the central amygdaloid nucleus modulates the parabrachial nucleus taste responses in rats
Kang Yi, Yan Jianqun, Huang Tao
Department of Physiology,Key Laboratory of Environment and Genes Related to Diseases,Ministry of Education,Xi'an Jiaotong University School of Medicine.Xi'an 710061,Shaanxi
Abstract
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 CeA are involved in this modulation, the effects of microinjection of 6-cyano-7-nitro-quinoxaline-2, 3-dione (CNQX), an AMPA receptor antagonist, into the CeA on 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 involve the descending modulation in the PBN taste neurons.
Key words: Parabrachial nucleus;Central nucleus of the amygdala;Taste;Microinjection;6-cyano-7-nitro-quinoxaline-2,3-dione
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引用本文:
康怡, 闫剑群, 黄涛. 阻断大鼠杏仁中央核AMPA受体对臂旁核味觉反应的影响[J]. 生理学报 2004; 56 (6): .
Kang Yi, Yan Jianqun, Huang Tao. Blocking of AMPA receptors in the central amygdaloid nucleus modulates the parabrachial nucleus taste responses in rats. Acta Physiol Sin 2004; 56 (6): (in Chinese with English abstract).