ACTIVITY AND THE CONTROL OF GANGLION-CELL DEATH IN THE RAT RETINA
ACTIVITY AND THE CONTROL OF GANGLION-CELL DEATH IN THE RAT RETINA
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DOI：
10.1073/pnas.81.17.5589
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发表时间：
1984-01-01
期刊：
影响因子：
--
通讯作者：
COWAN, WM
中科院分区：
文献类型：
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作者：
FAWCETT, JW;OLEARY, DDM;COWAN, WM
在新生大鼠中，每个视网膜主要投射到对侧上级丘，但也有稀疏的投射到整个同侧上级丘。在出生后的第一个2周，同侧投射通常局限于上级丘的吻内侧部分。这种投射的限制是由于同侧投射的视网膜神经节细胞的优先死亡，并且显然是来自2只眼睛的光纤之间竞争的结果，因为它可以通过在出生时对侧眼睛的眼球摘除来防止。为了确定电活动是否在同侧视网膜丘投射的正常限制中起作用，在出生后的前2周期间，将Na通道阻断剂河豚毒素施用于一只或两只眼睛。在1只眼睛中，河豚毒素阻断活性导致对侧眼睛在同侧上级丘中的稀疏投射持续存在，并且在该眼睛中通常已经死亡的同侧投射视网膜神经节细胞的大量存活。当双眼用河豚毒素治疗时，两侧的同侧投射均无限制。这些研究结果表明，视网膜神经节细胞轴突之间的竞争（无论是终端空间或一个必要的营养因子），这通常会导致视网膜神经节细胞死亡和同侧视网膜丘投影的限制，是以某种方式介导的电活动。
In newborn rats each retina projects principally to the contralateral superior colliculus, but there is also a sparse projection to the whole of the ipsilateral superior colliculus. During the first 2 wk postnatally the ipsilateral projection normally becomes restricted to the rostromedial part of the superior colliculus. The restriction of this projection is due to the preferential death of ipsilaterally projecting retinal ganglion cells and is apparently the result of competition between optic fibers from the 2 eyes, since it can be prevented by enucleation of the opposite eye at birth. To determine if electrical activity plays a role in the normal restriction of the ipsilateral retinocollicular projection, the Na channel-blocking agent tetrodotoxin was administered to one or both eyes during the first 2 wk postnatally. Tetrodotoxin blockade of activity in 1 eye resulted in the persistence of a sparse projection from the opposite eye throughout the ipsilateral superior colliculus and the survival of a substantial number of the ipsilaterally projecting retinal ganglion cells in that eye that would normally have died. When both eyes were treated with tetrodotoxin no restriction of the ipsilateral projection was seen on either side. These findings suggest that the competition between retinal ganglion cell axons (either for terminal space or an essential trophic factor), which normally leads to retinal ganglion cell death and the restriction of the ipsilateral retino-collicular projection, is mediated in some way by electrical activity.