Activity-dependent regulation of mitochondrial motility by calcium and Na/K-ATPase at nodes of Ranvier of myelinated nerves.
Activity-dependent regulation of mitochondrial motility by calcium and Na/K-ATPase at nodes of Ranvier of myelinated nerves.
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通过钙神经的ranvier节点对线粒体运动的活性依赖性调节。
DOI：
10.1523/jneurosci.4551-09.2010
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发表时间：
2010-03-10
期刊：
影响因子：
--
通讯作者：
Chiu SY
中科院分区：
文献类型：
--
作者：
Zhang CL;Ho PL;Kintner DB;Sun D;Chiu SY
The node of Ranvier is a tiny segment of a myelinated fiber with various types of specializations adapted for generation of high speed nerve impulses. It is ionically specialized with respect to ion channel segregation and ionic fluxes, and metabolically specialized in ionic pump expression and mitochondrial density augmentation. This report examines the interplay of three important parameters (calcium fluxes, Na pumps, mitochondrial motility) at nodes of Ranvier in frog during normal nerve activity. First, we used calcium dyes to resolve a highly localized elevation in axonal calcium at a node of Ranvier during action potentials, and showed that this calcium elevation retards mitochondrial motility during nerve impulses. Second, we found, surprisingly, that physiologic activation of the Na pumps retards mitochondrial motility. Blocking Na pumps alone greatly prevents action potentials from retarding mitochondrial motility, which reveals that mitochondrial motility is coupled to Na/K-ATPase. In conclusion, we suggest that during normal nerve activity, Ca elevation and activation of Na/K-ATPase act, possibly in a synergistic fashion, to recruit mitochondria to a node of Ranvier to match metabolic needs.
