Low-voltage-activated A-current controls the firing dynamics of mouse hypothalamic orexin neurons

被引：27

作者：

Burdakov, D

Alexopoulos, H

Vincent, A

Ashcroft, FM

机构：

[1] Univ Oxford, Physiol Lab, Oxford OX1 3PT, England

[2] Univ Oxford, Weatherall Inst Mol Med, Oxford OX1 3PT, England

来源：

EUROPEAN JOURNAL OF NEUROSCIENCE | 2004年 / 20卷 / 12期

基金：

英国惠康基金;

关键词：

A-current; hypocretin; hypothalamus; orexin; wakefulness;

D O I：

10.1111/j.1460-9568.2004.03815.x

中图分类号：

Q189 [神经科学];

学科分类号：

071006 ;

摘要：

The activity of hypothalamic neurons that release the neuropeptides orexin-A and orexin-B is essential for normal wakefulness. Orexin neurons fire spontaneously and are hyperpolarized and inhibited by physiological neuromodulators, but the intrinsic determinants of their electrical activity are poorly understood. We show that mouse orexin neurons coexpress orexin-A and orexin-B, and possess a low-voltage-activated A-type K+ current (A-current) likely to be composed of Kv4.3 subunits. The A-current enhances the inhibitory influence of hyperpolarizing currents via two mechanisms: by delaying the resumption of spiking after hyperpolarization and by increasing the slope of the relation between the firing frequency and injected current. These results identify an important determinant of the firing dynamics of orexin neurons, and support the idea that the A-current can control neuronal gain.

引用

页码：3281 / 3285

页数：5

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