Voltage-gated Na(+) channels in chemoreceptor afferent neurons--potential roles and changes with development.
Voltage-gated Na(+) channels in chemoreceptor afferent neurons--potential roles and changes with development.
复制标题
DOI：
10.1016/j.resp.2012.08.009
复制
发表时间：
2013-01-01
影响因子：
2.3
通讯作者：
Donnelly, David F.
中科院分区：
文献类型：
--
作者：
Donnelly, David F.
颈动脉体化学感受器增加其动作电位（AP）活动，以响应动脉氧分压的降低，并且这种响应在出生后增加。初始转导位点可能是血管球细胞，其对缺氧作出反应，细胞内钙增加并分泌多种神经递质。这种分泌转化为AP尖峰水平是由传入神经末梢的兴奋性决定的，其主要由Na+通道激活的电压依赖性决定。在这篇综述中，我们研究了Na+通道的生物物理特性存在于索马的化学感受器传入神经元的假设，类似的通道存在于神经末梢。该电流的电压依赖性与单个Na+通道亚型一致，其在静息电位附近活化，并且约60-70%的通道在静息电位附近处于非活性状态。由于从非活动/打开或关闭/打开状态的转变，通道打开可以用于放大外部去极化事件或通过自身生成AP。在出生后的前两周内，Na+通道激活电压向更负的电位移动，从而增强Na+通道对去极化事件的放大作用，并增加通道转换产生的膜噪声。这可能是一个显着的贡献者在出生后时期的化学感受器活性的成熟。
Carotid body chemoreceptors increase their action potential (AP) activity in response to a decrease in arterial oxygen tension and this response increases in the post-natal period. The initial transduction site is likely the glomus cell which responds to hypoxia with an increase in intracellular calcium and secretion of multiple neurotransmitters. Translation of this secretion to AP spiking levels is determined by the excitability of the afferent nerve terminals that is largely determined by the voltage-dependence of activation of Na+ channels. In this review, we examine the biophysical characteristics of Na+ channels present at the soma of chemoreceptor afferent neurons with the assumption that similar channels are present at nerve terminals. The voltage dependence of this current is consistent with a single Na+ channel isoform with activation around the resting potential and with about 60-70% of channels in the inactive state around the resting potential. Channel openings, due to transitions from inactive/open or closed/open states, may serve to amplify external depolarizing events or generate, by themselves, APs. Over the first two post-natal weeks, the Na+ channel activation voltage shifts to more negative potentials, thus enhancing the amplifying action of Na+ channels on depolarization events and increasing membrane noise generated by channel transitions. This may be a significant contributor to maturation of chemoreceptor activity in the post-natal period.
登录
查看更多内容
影响因子：
3.3
作者：
Donnelly, DF
通讯作者：
Donnelly, DF
DOI：
10.1016/j.bbrc.2004.07.081
发表时间：
2004-09-10
影响因子：
3.1
作者：
Buttigieg, J;Nurse, CA
通讯作者：
Nurse, CA
影响因子：
2.9
作者：
Fitzgerald, Robert S.;Shirahata, Machiko;Kostuk, Eric
通讯作者：
Kostuk, Eric
影响因子：
5.5
作者：
Brock, JA;McLachlan, EM;Belmonte, C
通讯作者：
Belmonte, C
影响因子：
3.4
作者：
Chow, CC;White, JA
通讯作者：
White, JA