Response properties of long-range axon-bearing amacrine cells in the dark-adapted rabbit retina
Response properties of long-range axon-bearing amacrine cells in the dark-adapted rabbit retina
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暗适应兔视网膜长程轴突无长突细胞的反应特性
DOI：
10.1017/s0952523800008506
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发表时间：
1996
影响因子：
1.9
通讯作者：
W. Taylor
中科院分区：
文献类型：
--
作者：
W. Taylor
摘要哺乳动物视网膜中的无长突细胞在电生理学研究中很少见到，因此对其生理特性知之甚少。采用膜片钳电极记录暗适应兔视网膜中两个轴突无长突细胞的光反应。将记录的细胞染色，并观察形态。两种细胞都能够产生动作电位。在一种情况下，平均去极化和动作电位频率之间的线性关系被证明。细胞有一个近端的树突状乔木和形态上不同的，更大的轴突终末系统。中心反应的感受野与树突状乔木同延，因此也比轴突终末系统小得多。中枢反应被抑制周围的抑制激活。这两个细胞响应中心照明与向内的电流变得更加短暂的照明点的大小增加。有人建议，轴突轴承无长突细胞接收输入的树突状乔木定义的感受野，并分配其输出在一个更广泛的轴突终端系统，最有可能通过动作电位。
Abstract Axon-bearing amacrine cells in mammalian retinae are encountered relatively infrequently during electrophysiological investigations, and thus very little is known about their physiological properties. Patch-clamp electrodes were used to record light responses from two axon-bearing amacrine cells in flat-mounted, dark-adapted rabbit retina. The recorded cells were stained, and the morphology visualized. Both cells were capable of generating action potentials. In one case, a linear relationship between mean depolarization and action-potential frequency was demonstrated. The cells had a proximal dendritic arbor and a morphologically distinct, much larger axon terminal system. The receptive field of the center response was coextensive with the dendritic arbor, and thus also much smaller than the axon terminal system. The center response was suppressed by activation of an inhibitory surround. Both cells responded to center illumination with an inward current which became more transient as the size of the illuminating spot was increased. It is suggested that axon-bearing amacrine cells receive input over a receptive field defined by the dendritic arbor, and distribute their output over a much more extensive axon terminal system, most probably via action potentials.