中文摘要：

背景 L-glutamate (L-GLU ) 是在原子核 ambiguus (NA ) 的主要 neurotransmitter，它能调制呼吸，动脉的压力，心率，等等。这研究在一个乳胶汽球与一个压力变换器连接了的 rats.Methods 在胃的活动性上调查了 L-GLU microinjected 的效果和机制进 NA 为胃的活动性的连续记录通过 forestomach 被插入到幽门。在 5 以内的胃的收缩波浪的全部的振幅，全部的持续时间，和活动性索引在 microinjection 前并且在 microinjection 以后纪录是 measured.Results L-GLU (在 50 nl 正常的 5 nmol ， 10 nmol 和 20 nmol 盐( PS )分别地)进正确 NA 的 microinjected 显著地禁止了胃的活动性，当时 microinjection 生理在一样的位置和一样的体积盐没改变胃的活动性。禁止的效果被 D-2-amino-5-phophonovalerate 堵住( D-AP5 ， 5 nmol ，在 50 nl PS )，特定的 N-methyl-D-aspartic 酸( NMDA )受体对手，但是没被6-cyaon-7-nitroquinoxaline-2,3-( 1H,4H )影响 -dione ( CNQX )( 5 nmol ，在 50 nl PS )， non-NMDA ionotropic 受体对手。双边的 subdiaphragmatic vagotomy 由 L-GLU 的 microinjection 废除了禁止的效果进 NA。进 NA 的 L-GLU 的结论 Microinjection 通过特定的 NMDA 受体活动，不是 non-NMDA 受体活动禁止胃的活动性，并且传出小径是 vagal 神经。

英文摘要：

Background L-glutamate （L-GLU） is a major neurotransmitter in the nucleus ambiguus （NA）, which can modulate respiration, arterial pressure, heart rate, etc. This study investigated the effects and mechanisms of L-GLU microinjected into NA on gastric motility in rats. Methods A latex balloon connected with a pressure transducer was inserted into the pylorus through the forestomach for continuous recording of the gastric motility. The total amplitude, total duration, and motility index of gastric contraction waves within 5 minutes before microinjection and after microinjection were measured. Results L-GLU （5 nmol, 10 nmol and 20 nmol in 50 nl normal saline （PS） respectively） microinjected into the right NA significantly inhibited gastric motility, while microinjection of physiological saline at the same position and the same volume did not change the gastric motility. The inhibitory effect was blocked by D-2-amino-5-phophonovalerate （D-AP5, 5 nmol, in 50 nl PS）, the specific N-methyI-D-aspartic acid （NMDA） receptor antagonist, but was not influenced by 6-cyaon-7-nitroquinoxaline-2,3-（1H,4H）-dione （CNQX） （5 nmol, in 50 nl PS）, the non-NMDA ionotropic receptor antagonist. Bilateral subdiaphragmatic vagotomy abolished the inhibitory effect by microinjection of L-GLU into NA. Conclusions Microinjection of L-GLU into NA inhibits the gastric motility through specific NMDA receptor activity, not non-NMDA receptor activity, and the efferent pathway is the vagal nerves.