Ashikawa H, Furuya N, Yabe T
Department of Otolaryngology, Teikyo University School of Medicine, Tokyo, Japan.
Acta Otolaryngol. 1991;111(6):999-1005. doi: 10.3109/00016489109100748.
Pause neurons (PNs), found in the pontine raphe nuclei, are important in the regulation of fast eye movements. The present study focuses on transmitters regulating the activity of the PNs. Extracellular spikes of single PNs and ocular motor nerve discharges were simultaneously recorded during horizontal vestibular nystagmus in the alert cat. Several transmitter candidates were iontophoretically applied, while methysergide, a serotonin antagonist, was administered both systemically and topically. The following data supported the conclusion that PNs are probably under the control of two different types of neurons, and the firing of PNs may be caused partly by GABAergic, but not by glycinergic neurons: 1) serotonin markedly decreased the spontaneous firing of the PNs; 2) methysergide abolished the inhibitory effect of serotonin on the PN firing; however, a pause pattern was maintained under this condition; 3) GABA moderately suppressed the firing but only in 25% of PNs; and 4) glycine hardly changed the PN firing in any case examined.
位于脑桥中缝核的暂停神经元（PNs）在快速眼动的调节中起重要作用。本研究聚焦于调节PNs活性的递质。在警觉猫的水平前庭眼震期间，同时记录单个PNs的细胞外锋电位和眼球运动神经放电。通过离子电泳法施加几种候选递质，同时全身和局部给予5-羟色胺拮抗剂麦角新碱。以下数据支持这样的结论：PNs可能受两种不同类型神经元的控制，PNs的放电可能部分由γ-氨基丁酸能神经元引起，而非甘氨酸能神经元：1）5-羟色胺显著降低PNs的自发放电；2）麦角新碱消除了5-羟色胺对PNs放电的抑制作用；然而，在此条件下仍维持暂停模式；3）γ-氨基丁酸适度抑制放电，但仅在25%的PNs中出现；4）在任何检查的情况下，甘氨酸几乎不改变PNs的放电。
