Taylor J S, Willshaw D J, Gaze R M
J Embryol Exp Morphol. 1985 Feb;85:225-38.
In Xenopus embryos of stage 30 the right eye was translocated, without rotation, to a left host orbit. Shortly after metamorphosis the visuotectal projection through the operated eye was mapped electrophysiologically and shown to be normal dorsoventrally but reversed nasotemporally. Labelling of small groups of retinal axons with HRP showed that the fibre trajectories from dorsal and ventral retina were normal, whereas fibres from nasally placed retina had diencephalic pathways and tectal terminations typical and temporal fibres, and fibres from temporally placed retina had diencephalic pathways and tectal terminations typical of nasal fibres. Thus from just beyond the chiasma the fibres had already achieved the major uniaxial rearrangement necessary to establish a normal tract distribution despite the eye translocation. The fibre rearrangement required to permit the formation of a nasotemporally inverted visuotectal projection appears, therefore, to occur not on the tectum or in the optic tract, but either within the nerve or at the chiasma.
在第30阶段的非洲爪蟾胚胎中，右眼在不旋转的情况下被转移到左侧宿主眼眶。变态后不久，通过手术眼的视顶盖投射用电生理学方法进行了映射，结果显示其在背腹方向上是正常的，但在鼻颞方向上是反转的。用辣根过氧化物酶（HRP）标记小群视网膜轴突表明，来自背侧和腹侧视网膜的纤维轨迹是正常的，而来自鼻侧视网膜的纤维具有典型的间脑通路和顶盖终末，如同颞侧纤维一样，并且来自颞侧视网膜的纤维具有典型的鼻侧纤维的间脑通路和顶盖终末。因此，尽管眼睛发生了移位，但从交叉处稍远处起，纤维就已经完成了建立正常束分布所需的主要单轴重排。所以，允许形成鼻颞反转的视顶盖投射所需的纤维重排似乎不是发生在顶盖或视束中，而是发生在神经内或交叉处。
