期刊
JOURNAL OF NEUROSCIENCE METHODS
卷 208, 期 2, 页码 119-127出版社
ELSEVIER
DOI: 10.1016/j.jneumeth.2012.05.005
关键词
Unmyelinated axons; Grease-gap; Membrane potential
资金
- Norwegian node of the International Neuroinformatics Coordinating Facility
We investigated the ability of a grease-gap method to record fast and slow changes of the membrane potential from bundles of gray matter axons. Their membrane potentials are of particular interest because these axons are different from most axons that have been investigated using intra-axonal or gap techniques. One of the main differences is that gray matter axons typically have closely spaced presynaptic specializations, called boutons or varicosities, distributed along their entire paths. In response to electrical activation of bundles of parallel fiber axons we were able to record small (128-416 mu V) but stable signals that we show most likely represented a fraction of the trans-membrane action potentials. A less-than 100% fraction prevents measurements of absolute values for membrane potentials, but the good signal-to-noise ratio (typically 10-16) allows detection of changes in resting membrane potential, action potentials and their after-potentials. Because very little is known about the shape of action potentials and after-potentials in these axons we used several independent methods to make it likely that the grease-gap signal was of intra-axonal origin. We demonstrate the utility of the method by showing that the action potentials in cerebellar parallel fibers and hippocampal Schaffer collaterals had a slowly decaying, depolarized after-potential. The method is ideal for pharmacological tests, which we demonstrate by showing that the slow after-potential was sensitive to 4-AP, and that the membrane potential was reduced by 200 mu M Ba2+. (C) 2012 Elsevier B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据