Alford S, Grillner S
Nobel Institute for Neurophysiology, Karolinska Institutet, Stockholm, Sweden.
Brain Res. 1990 Jan 8;506(2):297-302. doi: 10.1016/0006-8993(90)91266-j.
The motor pattern underlying locomotion in the lamprey is activated and maintained by excitatory amino acid neurotransmission. The quinoxalinediones 6,7-dinitroquinoxaline-2,3-dione (DNQX) and 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) are potent and selective antagonists of non-N-methyl-D-aspartate (NMDA) receptors in the mammalian central nervous system. In the lamprey, these compounds are now shown to block fast excitatory synaptic potentials elicited in neurones of the spinal ventral horn. They selectively antagonise responses to the application of selective kainate and quisqualate receptor agonists (kainate and alpha-amino-3-hydroxy-5-methyl-4-isoxalone (AMPA)) but do not influence NMDA receptor-mediated responses. Additionally, it is shown that the activation of NMDA receptors is sufficient to elicit and maintain fictive locomotion after blockade of non-NMDA receptors with either DNQX or CNQX. Conversely, activation of quisqualate receptors with AMPA, but not quisqualate leads to fictive locomotion with properties much like that activated by kainate.
七鳃鳗运动的基础运动模式由兴奋性氨基酸神经传递激活并维持。喹喔啉二酮类化合物6,7 - 二硝基喹喔啉 - 2,3 - 二酮（DNQX）和6 - 氰基 - 7 - 硝基喹喔啉 - 2,3 - 二酮（CNQX）是哺乳动物中枢神经系统中非N - 甲基 - D - 天冬氨酸（NMDA）受体的强效选择性拮抗剂。在七鳃鳗中，现已表明这些化合物可阻断脊髓腹角神经元中引发的快速兴奋性突触电位。它们选择性地拮抗对选择性海人藻酸和quisqualate受体激动剂（海人藻酸和α - 氨基 - 3 - 羟基 - 5 - 甲基 - 4 - 异恶唑酮（AMPA））应用的反应，但不影响NMDA受体介导的反应。此外，研究表明在用DNQX或CNQX阻断非NMDA受体后，NMDA受体的激活足以引发并维持虚拟运动。相反，用AMPA激活quisqualate受体，但不是quisqualate，会导致具有与海人藻酸激活的运动非常相似特性的虚拟运动。
