Dedek Karin, Pandarinath Chethan, Alam Nazia M, Wellershaus Kerstin, Schubert Timm, Willecke Klaus, Prusky Glen T, Weiler Reto, Nirenberg Sheila
Department of Neurobiology, University of Oldenburg, Oldenburg, Germany.
PLoS One. 2008 Mar 5;3(3):e1714. doi: 10.1371/journal.pone.0001714.
The visual system can adjust itself to different visual environments. One of the most well known examples of this is the shift in spatial tuning that occurs in retinal ganglion cells with the change from night to day vision. This shift is thought to be produced by a change in the ganglion cell receptive field surround, mediated by a decrease in the coupling of horizontal cells.
METHODOLOGY/PRINCIPAL FINDINGS: To test this hypothesis, we used a transgenic mouse line, a connexin57-deficient line, in which horizontal cell coupling was abolished. Measurements, both at the ganglion cell level and the level of behavioral performance, showed no differences between wild-type retinas and retinas with decoupled horizontal cells from connexin57-deficient mice.
CONCLUSION/SIGNIFICANCE: This analysis showed that the coupling and uncoupling of horizontal cells does not play a dominant role in spatial tuning and its adjustability to night and day light conditions. Instead, our data suggest that another mechanism, likely arising in the inner retina, must be responsible.
视觉系统能够自我调节以适应不同的视觉环境。其中一个最著名的例子是，随着从夜间视觉转变为日间视觉，视网膜神经节细胞的空间调谐会发生变化。这种转变被认为是由神经节细胞感受野周围环境的变化所引起的，而这种变化是由水平细胞之间耦合的减少介导的。
方法/主要发现：为了验证这一假设，我们使用了一种转基因小鼠品系，即连接蛋白57缺陷型品系，其中水平细胞的耦合被消除。在神经节细胞水平和行为表现水平上的测量结果表明，野生型视网膜与来自连接蛋白57缺陷型小鼠的水平细胞解耦的视网膜之间没有差异。
结论/意义：该分析表明，水平细胞的耦合和解耦在空间调谐及其对昼夜光照条件的适应性方面并不起主导作用。相反，我们的数据表明，可能源于视网膜内层的另一种机制必定是其原因所在。
