家兔延髓孤束核神经元NMDA受体和非NMDA受体在急性缺氧中的作用

目的探讨成年家兔延髓孤束核（NTS）神经元上N-甲基-D-天冬氨酸（NMDA）受体和非NMDA受体在急性缺氧引起的外周化学感受器兴奋性传导中的作用。方法通过显微注射技术向家兔NTS内注射NMDA受体拮抗剂2-氨基-5-磷酸戊酸（AP-5）和（或）非NMDA受体拮抗剂6．7-二硝基喹诺林-2．3-二酮（DNQX），观察其对急性缺氧时膈神经放电变化的影响。结果应用AP-5或DNQX对缺氧引起的呼吸增强均产生了抑制效应，两种受体拮抗剂之间有交互作用。结论哺乳动物NTS神经元上的NMDA受体和非NMDA受体在介导急性缺氧时外周化学感受性信号向中枢的传递中均发挥作用，NMDA受体尤为重要。两种受体有协同性作用。

Effect of N-methyl-D-aspartate (NMDA) and non-NMDA glutamate receptors located in the nucleus tractus solitarii neuron in the peripheral chemosensitive afferent inputs caused by acute hypoxia

Objective: To investigate the role of N-methyl-D-aspartate(NMDA) and non-NMDA glutamate receptors located in the nucleus tractus solitarii(NTS) neuron in the peripheral chemosensitive afferent inputs caused by acute hypoxia.Methods: Experiments were done on rabbits to observe the effects of NMDA receptor antagonist 2-amino-5-phosphonovaleric acid(AP-5) and non-NMDA receptor antagonist 6,7-dinitro-quinoxaline-2,3-dione(DNQX) on the phrenic nerve discharges in the process of acute hypoxia by microinjecting the two antagonists into the NTS.Results: Both AP-5 and DNQX had depression effects on the hyperpnea caused by acute hypoxia,and interacted with each other.Conclusion: NMDA and non-NMDA receptors located in the NTS may have separate effects and a cooperative influence on the peripheral chemosensitive afferent inputs caused by acute hypoxia,and NMDA receptor plays a more significant role.