Voltage-gated Na+ channels enhance the temporal filtering properties of electrosensory neurons in the torus
Voltage-gated Na+ channels enhance the temporal filtering properties of electrosensory neurons in the torus
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DOI：
10.1152/jn.00294.2003
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发表时间：
2003-08-01
影响因子：
2.5
通讯作者：
Rose, GJ
中科院分区：
文献类型：
--
作者：
Fortune, ES;Rose, GJ
再生过程增强突触后电位（PSP）的幅度和行为相关的时间过滤在超过三分之一的Eigenmannia的圆枕的电感觉神经元。体内电流钳细胞内记录的数据表明，这些“再生PSP”可以根据其半振幅持续时间分为两组：恒定持续时间（CD）和可变持续时间（VD）PSP。CD PSP的半振幅持续时间在20和60 ms之间，不随刺激周期而变化。相比之下，VD PSP的半振幅持续时间变化的刺激周期性和范围从约10至500 ms。注射0.1 nA的正弦电流通过记录电极表明，CD PSP，而不是VD PSP可以引起单独的电压波动。此外，细胞内应用QX-314或QX-222可阻断CD PSP，而VD PSP则不能。这些体内数据表明，因此，CD PSP介导的电压依赖性Na+电导。
Regenerative processes enhance postsynaptic potential (PSP) amplitude and behaviorally relevant temporal filtering in more than one-third of electrosensory neurons in the torus semicircularis of Eigenmannia. Data from in vivo current-clamp intracellular recordings indicate that these "regenerative PSPs" can be divided in two groups based on their half-amplitude durations: constant duration (CD) and variable duration (VD) PSPs. CD PSPs have half-amplitude durations of between 20 and 60 ms that do not vary in relation to stimulus periodicity. In contrast, the half-amplitude durations of VD PSPs vary in relation to stimulus periodicity and range from approximately 10 to 500 ms. Injection of 0.1 nA sinusoidal current through the recording electrode demonstrated that CD PSPs and not VD PSPs can be elicited by voltage fluctuations alone. In addition, CD PSPs were blocked by intracellular application of either QX-314 or QX-222, whereas VD PSPs were not. These in vivo data suggest, therefore, that CD PSPs are mediated by voltage-dependent Na+ conductances.