Miller K D, Chapman B, Stryker M P
Department of Physiology, University of California, San Francisco 94143-0444.
Proc Natl Acad Sci U S A. 1989 Jul;86(13):5183-7. doi: 10.1073/pnas.86.13.5183.
We have investigated the role of the N-methyl-D-aspartate (NMDA) receptor, a subtype of glutamate receptor, in the responses of cells in adult cat visual cortex. After intracortical infusion of the NMDA receptor antagonist DL-2-amino-5-phosphonovalerate (DL-APV) for one day, iontophoretic responses to NMDA, to kainate, and to quisqualate revealed a receptor blockade specific to NMDA receptors and extending several millimeters from the cannula. In this region, neuronal responses to visual stimulation were profoundly suppressed, in a manner strongly correlated with the degree of NMDA receptor blockade. Neither NMDA receptor blockade nor activity suppression was caused by the inactive stereoisomer L-APV. Hence, we conclude that NMDA receptors make a major contribution to normal excitatory transmission in adult visual cortex.
我们研究了谷氨酸受体亚型N-甲基-D-天冬氨酸(NMDA)受体在成年猫视觉皮层细胞反应中的作用。在皮层内注入NMDA受体拮抗剂DL-2-氨基-5-磷酸缬氨酸(DL-APV)一天后,对NMDA、对海人藻酸和对quisqualate的离子电渗反应显示出对NMDA受体的特异性阻断,且从插管处延伸数毫米。在该区域,神经元对视觉刺激的反应受到深度抑制,其抑制方式与NMDA受体阻断程度密切相关。非活性立体异构体L-APV既不会导致NMDA受体阻断,也不会引起活性抑制。因此,我们得出结论,NMDA受体对成年视觉皮层的正常兴奋性传递起主要作用。