EVIDENCE THAT ACTIVATION OF N-METHYL-D-ASPARTATE (NMDA) AND NON-NMDA RECEPTORS WITHIN THE NUCLEUS-TRACTUS-SOLITARII TRIGGERS SWALLOWING
EVIDENCE THAT ACTIVATION OF N-METHYL-D-ASPARTATE (NMDA) AND NON-NMDA RECEPTORS WITHIN THE NUCLEUS-TRACTUS-SOLITARII TRIGGERS SWALLOWING
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DOI：
10.1016/0014-2999(91)90323-i
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发表时间：
1991-08-16
影响因子：
5
通讯作者：
JEAN, A
中科院分区：
文献类型：
--
作者：
KESSLER, JP;JEAN, A
吞咽是由位于孤束核（NTS）内的神经元产生的模式化运动活动。先前的实验已经表明，在NTS内给予兴奋性氨基酸诱导吞咽。本研究旨在确定参与这种效应的受体亚型。在去大脑大鼠的孤束核内压力显微注射L-谷氨酸（10-100 pmol）、使君子酸（0.1-10 pmol）和N-甲基-D-天冬氨酸（NMDA，0.1-10 pmol）。谷氨酸和使君子酸微量注射引起短系列的吞咽，而NMDA微量注射诱导持久的，有节奏的吞咽。用选择性NMDA拮抗剂DL-2-amino-5-phosphonovalerate（50 pmol）预处理，几乎完全抑制了NMDA（10 pmol）引起的反应，但未诱导谷氨酸（25 pmol）或使君子酸（10 pmol）引起的吞咽显著改变。预处理与6-氰基-7-硝基喹喔啉-2，3-二酮（50 pmol），非NMDA受体的选择性阻断剂，抑制吞咽引起的谷氨酸和强烈抑制的反应引起的使君子酸显微注射。相同的预处理诱导的NMDA引起的吞咽只有轻微的修改。这些数据表明，吞咽可以通过激活位于NTS内的NMDA或非NMDA受体来触发，因此表明这两种受体亚型可能参与生理条件下引起的吞咽。
Swallowing is a patterned motor activity generated by neurons located within the nucleus tractus solitarii (NTS). Previous experiments have shown that administration of excitatory amino acids within the NTS induces swallowing. The present study was undertaken to identify the receptor subtypes involved in this effect. Pressure microinjections of L-glutamate (10-100 pmol), quisqualate (0.1-10 pmol) and N-methyl-D-aspartate (NMDA, 0.1-10 pmol) were performed into the NTS of decerebrate rats. Glutamate and quisqualate microinjections elicited short series of swallows while NMDA microinjections induced long-lasting, rhythmic swallowing. Pretreatment with the selective NMDA antagonist, DL-2-amino-5-phosphonovalerate (50 pmol), almost completely suppressed the response elicited by NMDA (10 pmol) but did not induce a significant modification of swallowing triggered by either glutamate (25 pmol) or quisqualate (10 pmol). Pretreatment with 6-cyano-7-nitroquinoxaline-2,3-dione (50 pmol), a selective blocker of non-NMDA receptors, suppressed the swallows elicited by glutamate and strongly inhibited the response elicited by quisqualate microinjections. The same pretreatment induced only a slight modification of the swallowing elicited by NMDA. These data demonstrate that deglutition can be triggered by activating either NMDA or non-NMDA receptors localized within the NTS, and therefore suggest that both receptor subtypes may be involved in swallowing elicited under physiological conditions.