Characteristics of bipolar-bipolar coupling in the carp retina
Characteristics of bipolar-bipolar coupling in the carp retina
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鲤鱼视网膜双极-双极耦合特征
DOI：
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发表时间：
1988
期刊：
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通讯作者：
T. Kujiraoka
中科院分区：
文献类型：
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作者：
Takehiko Saito;T. Kujiraoka
通过细胞内记录和荧光黄染料注射的方法，在光适应性鲤鱼视网膜中识别了ON和OFF双极细胞。通过测量不同直径的中心点获得的反应幅度来确定感受野中心，ON双极细胞为0.3-1.0 mm，OFF双极细胞为0.3-0.4 mm。这些中央感受野值远大于树突状领域的直径测量的组织学方法。从相邻的双极细胞对同时进行细胞内记录。将任一极性的电流注入双极细胞对的一个成员中，引起另一个双极细胞中的符号保存的持续电位变化。去极化和超极化电流的耦合效率几乎相同。耦合的双极电池的最大间隔约为130微米。这种电耦合是相互的和总结性的，并且在类似功能和形态的细胞类型中观察到。在34个染色细胞中的4个中观察到染料偶联。这些结果有力地表明，在双极细胞水平上存在信号的空间总和，这使得它们的中央感受野比它们的树突野大得多。
ON and OFF bipolar cells were identified in the light-adapted carp retina by means of intracellular recording and Lucifer yellow dye injection. The receptive field centers, determined by measuring the response amplitudes obtained by centered spots of different diameters, were 0.3-1.0 mm for ON bipolar cells and 0.3-0.4 mm for OFF bipolar cells. These central receptive field values were much larger than the dendritic field diameters measured by histological methods. Simultaneous intracellular recordings were made from pairs of neighboring bipolar cells. Current of either polarity injected into one member of a bipolar cell pair elicited a sign-conserving, sustained potential change in the other bipolar cell. The coupling efficiency was nearly identical for both depolarizing and hyperpolarizing currents. The maximum separation of coupled bipolar cells was approximately 130 microns. This electrical coupling was reciprocal and summative, and it was observed in cell types of similar function and morphology. Dye coupling was observed in 4 out of 34 stained cells. These results strongly suggest that there is a spatial summation of signals at the level of bipolar cells, which makes their central receptive fields much larger than their dendritic fields.