Felix D, Ehrenberger K
Division of Neurobiology, University of Berne, Switzerland.
Eur Arch Otorhinolaryngol. 1991;248(8):429-31. doi: 10.1007/BF00627627.
With the aid of microiontophoretic techniques we tested the action of N-methyl-D-aspartate (NMDA) and an NMDA antagonist in the dendritic region of inner hair cell afferent fibers. In the majority of units tested NMDA enhanced the spontaneous firing rate. Furthermore, the activation of NMDA receptors triggered unusual depolarization patterns: (1) slow-frequency oscillation with a periodicity of about 3/min; (2) a fast oscillatory pattern of burst firing with a rhythmic interburst frequency of about 2/s. These findings provide evidence for NMDA receptor properties in the cochlea similar to those of analog channels in the central nervous system.
借助微离子电泳技术，我们测试了N-甲基-D-天冬氨酸（NMDA）和一种NMDA拮抗剂在内毛细胞传入纤维树突区域的作用。在大多数被测试的单位中，NMDA提高了自发放电率。此外，NMDA受体的激活引发了不寻常的去极化模式：（1）频率约为3次/分钟的慢频率振荡；（2）爆发式放电的快速振荡模式，节律性爆发间期频率约为2次/秒。这些发现为耳蜗中NMDA受体特性提供了证据，类似于中枢神经系统中模拟通道的特性。
