Dashe J F, Davis T L
Department of Anatomy, University of Pennsylvania School of Medicine, Philadelphia 19104.
Brain Res. 1989 Dec 29;505(2):203-8. doi: 10.1016/0006-8993(89)91443-1.
Degenerating geniculate axon terminals in cat striate cortex have been previously described as electron-dense. After electrolytic lesion of the lateral geniculate nucleus, we observed degenerating terminals in layer 4 of striate cortex which were electron-lucent. The lucent terminals --which co-exist with the dense terminals--are characterized by a pale matrix, large size, distorted mitochondria, and a paucity of synaptic vesicles. They preferentially (82.5%) contact dendritic spines. Lucent terminals were common in layer 4, rare in layer 6, and absent from layers 1 through 3 and layer 5. This distribution is consistent with the projection of the lateral geniculate nucleus to the striate cortex. Thus, geniculate terminals undergo both the electron-lucent and electron-dense degeneration reactions in cat striate cortex, and the lucent terminals make a significant contribution to the amount of degeneration present. The relationship of lucent degeneration to other forms of degeneration is discussed.
猫纹状皮层中退化的膝状体轴突终末先前被描述为电子致密的。在外侧膝状体核进行电解损伤后，我们在纹状皮层第4层观察到电子透亮的退化终末。这些透亮终末——与致密终末共存——的特征是基质淡染、体积大、线粒体变形以及突触小泡稀少。它们优先（82.5%）与树突棘接触。透亮终末在第4层很常见，在第6层很少见，在第1至3层和第5层不存在。这种分布与外侧膝状体核向纹状皮层的投射一致。因此，在猫纹状皮层中，膝状体终末会经历电子透亮和电子致密两种退化反应，并且透亮终末对所呈现的退化量有显著贡献。文中还讨论了透亮退化与其他退化形式的关系。
