RECEPTIVE-FIELD PROPERTIES OF DISPLACED STARBURST AMACRINE CELLS CHANGE FOLLOWING AXOTOMY-INDUCED DEGENERATION OF GANGLION-CELLS
RECEPTIVE-FIELD PROPERTIES OF DISPLACED STARBURST AMACRINE CELLS CHANGE FOLLOWING AXOTOMY-INDUCED DEGENERATION OF GANGLION-CELLS
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DOI：
10.1017/s0952523800007409
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发表时间：
1995-01-01
影响因子：
1.9
通讯作者：
JENSEN, RJ
中科院分区：
文献类型：
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作者：
JENSEN, RJ
眼内注射荧光染料4，6-二脒基-2-苯基吲哚（DAPI）后，标记兔视网膜星状无长突细胞。从每只眼睛中取出一条视网膜，安装在落射荧光显微镜下的平台上，并用生理溶液灌注。钨微电极（用于细胞外记录）的尖端视觉定位在位于神经节细胞层中的DAPI标记的星状无长突细胞的细胞体附近。在正常视网膜和5-9个月前在视盘附近接受小电解损伤的视网膜中研究了移位的星爆状无长突细胞的光诱发反应。在正常视网膜中，几乎所有情况下，一个位于移位的星爆状无长突细胞感受野上方的小光点仅在光开始时诱发短暂的尖峰脉冲。当用一个大光斑或一个光环刺激时，许多细胞在光偏移处发出小的尖峰脉冲。在受损的视网膜，位移星爆无长突细胞的光反应记录在视网膜的神经节细胞退化的区域。所有的细胞都在一个小的中心光点的开始和偏移处产生大量的尖峰脉冲。大的光斑和光环也引起了这些细胞的强大的ON/OFF反应。这项研究的结果表明，移位星爆无长突细胞的感受场特性的变化后，轴突切断诱导的神经节细胞变性。这一发现表明，在神经节细胞变性后，视网膜中的突触传递或神经元的膜特性发生了变化。
Starburst amacrine cells in the rabbit retina were labeled following an intraocular injection of the fluorescent dye, 4,6,diamidino-2-phenylindole (DAPI). From each eye a strip of retina was removed, mounted on a platform beneath an epifluorescence microscope, and superfused with a physiological solution. The tip of a tungsten microelectrode (for extracellular recording) was visually positioned near the cell body of a DAPI-labeled starburst amacrine cell that was located in the ganglion cell layer. Light-evoked responses from the displaced starburst amacrine cells were studied in normal retinas and in retinas that had received a small electrolytic lesion near the optic disk 5-9 months beforehand. In normal retinas, a small spot of light centered over the receptive field of a displaced starburst amacrine cell in nearly all cases evoked a brief burst of spikes only at light onset. When stimulated with a large spot or an annulus of light, many cells gave a small burst of spikes at light offset. In lesioned retinas, the light responses of displaced starburst amacrine cells were recorded in areas of the retina where ganglion cells had degenerated. All cells responded with a large burst of spikes at the onset and offset of a small, centered spot of light. Large spots and annuli of light also evoked robust ON/OFF responses from these cells. The results from this study show that the receptive-field properties of displaced starburst amacrine cells change following axotomy-induced degeneration of ganglion cells. This finding indicates that changes in either synaptic transmission or the membrane properties of neurons occur in the retina following degeneration of ganglion cells.