Kirk D L, Johnstone B M
Department of Physiology, University of Western Australia, Nedlands.
Hear Res. 1993 May;67(1-2):20-34. doi: 10.1016/0378-5955(93)90228-s.
f2-f1, but not 2f1-f2, was reduced in amplitude during continuous stimulation of the test ear with the primary tones, and with single tones near the primary frequencies. Stimulation of the contralateral ear, either with broad band noise or with single tones near the primary frequencies, also reduced f2-f1. Ipsilateral and contralateral effects were additive and were restricted to the frequency range between about 2 kHz and 7 kHz. Contralateral, but not ipsilateral suppression, was blocked after systemic administration of strychnine. Ipsilateral suppression was eliminated by perfusion of the cochlea with tetrodotoxin. Both contralateral and ipsilateral suppression were abolished after perfusion of the cochlea with bicuculline. The results are evidence for a role for a GABA-ergic efferent system in the modulation of outer hair cell mechanics in the apical cochlea.
在用基频纯音以及接近基频的单音持续刺激测试耳时，f2 - f1的幅度减小，但2f1 - f2未减小。用宽带噪声或接近基频的单音刺激对侧耳，也会使f2 - f1减小。同侧和对侧效应是相加的，且局限于约2千赫兹至7千赫兹的频率范围。全身给予士的宁后，对侧而非同侧的抑制作用被阻断。用河豚毒素灌注耳蜗可消除同侧抑制。用荷包牡丹碱灌注耳蜗后，对侧和同侧抑制作用均被消除。这些结果证明了γ-氨基丁酸能传出系统在调节耳蜗顶部外毛细胞力学方面的作用。
