Visual information transmission in cat retinal ganglion cells with regenerated axons through the peripheral nerve graft.

在麻醉下，将成年猫的视神经完全切断，并移植自体坐骨神经。本实验首先通过记录再生轴突的单个单位活动，然后通过记录图形反转的视网膜电图来研究再生轴突的视网膜神经节细胞的视觉功能。结果总结如下。(1)在存活约60天时，将动物再次麻醉并固定。将移植神经解剖成细束，用银丝电极记录单个单位的活动。共记录了286个视觉反应单位，根据感受野特性将它们分为以下几组：142个是Y细胞，113个是X细胞，19个是W细胞，其余12个是未分类的。除中央X细胞视野扩大外，大多数单位的感受野中心大小正常。有一个明显的不对称的出现在ON和偏离中心的细胞，特别是在X细胞，没有关闭中心的细胞，而许多ON中心的细胞记录。(2)在视神经切断和神经移植手术后，再次麻醉猫，记录对正弦调制的垂直光栅的ERG反应。术后2 ~ 8周，图形反转ERG的振幅逐渐降低，但与视神经切断组相比，降低程度较轻，且逐渐降低，提示神经移植物对切断轴突的神经节细胞有一定的挽救作用。

Under anesthesia the optic nerve of adult cats was completely sectioned and an autologous sciatic nerve was grafted. Visual functions of the retinal ganglion cells with regenerated axons were studied first by recording single unit activities from regenerated axons and secondly by recording pattern reversed ERGs. Results are summarized below. (1) At about 60 days survival the animals were reanesthetized and immobilized. The grafted nerve was dissected into fine fascicles and single unit activities were recorded with silver wire electrodes. A total of 286 visually responsive units were recorded and they were classified into the following groups based on receptive field properties : 142 were Y cells, 113 were X cells, 19 were W cells and the rest 12 were unclassified. Receptive field center size was normal in most units except for central X cells with enlarged fields. There was a clear asymmetry in the occurrence of ON and Off center cells especially among X cells where there was no OFF center cells while many ON center cells were recorded. (2) After the same surgery of optic nerve section and nerve graft, cats were reanesthetized and ERGs were recorded in response to vertical gratings whose luminance was sinusoidally modulated. From 2 to 8 weeks after the surgery amplitudes of pattern reversed ERGs were gradually reduced but as compared with those of the optic nerve sectioned cats the reduction was mild and more gradual, suggesting some rescuing effects of the nerve graft on axotomized ganglion cells from retrograde cell death.