AN ALTERNATIVE PATHWAY FOR SIGNAL FLOW FROM ROD PHOTORECEPTORS TO GANGLION-CELLS IN MAMMALIAN RETINA
AN ALTERNATIVE PATHWAY FOR SIGNAL FLOW FROM ROD PHOTORECEPTORS TO GANGLION-CELLS IN MAMMALIAN RETINA
复制标题
DOI：
10.1073/pnas.92.23.10658
复制
发表时间：
1995-11-07
影响因子：
11.1
通讯作者：
BAYLOR, DA
中科院分区：
文献类型：
--
作者：
DEVRIES, SH;BAYLOR, DA
哺乳动物视网膜中的视杆细胞信号被认为通过电路到达神经节细胞：视杆细胞 - >视杆细胞去极化双极细胞 - >所有无长突细胞 - >视锥双极细胞 - >神经节细胞，一个可能的替代途径涉及连接视杆细胞和视锥细胞的间隙连接，电路是视杆 - >视锥细胞 - >视锥双极细胞 - >神经节细胞，目前尚不清楚第二条途径是否确实将视杆细胞信号传递给神经节细胞。我们用多电极阵列研究了离体兔视网膜中的信号流，这允许在用光刺激和/或暴露于药物的同时观察许多已识别的神经节细胞的活动。当杆状细胞和杆状去极化双极细胞之间的传输被谷氨酸激动剂2-氨基-4-磷酸丁酸（APB）阻断时，杆状细胞对所有中心和快速反应的偏离中心神经节细胞的输入如预期的那样显着减少。然而，在偏心迟缓和开-关方向选择性神经节细胞中，关闭反应仍然存在。推测这些反应是由涉及杆锥连接的替代途径产生的。这种 APE 抗性途径可能将主要的杆输入携带到偏心迟缓和开-关方向选择性神经节细胞。
Rod signals in the mammalian retina are thought to reach ganglion cells over the circuit rod --> rod depolarizing bipolar cell --> All amacrine cell --> cone bipolar cells --> ganglion cells, A possible alternative pathway involves gap junctions linking the rods and cones, the circuit being rod --> cone --> cone bipolar cells --> ganglion cells, It is not clear whether this second pathway indeed relays rod signals to ganglion cells. We studied signal flow in the isolated rabbit retina with a multielectrode array, which allows the activity of many identified ganglion cells to be observed simultaneously while the preparation is stimulated with light and/or exposed to drugs, When transmission between rods and rod depolarizing bipolar cells was blocked by the glutamate agonist 2-amino-4-phosphonobutyric acid (APB), rod input to all On-center and briskly responding Off-center ganglion cells was dramatically reduced as expected. Off responses persisted, however, in Off-center sluggish and On-Off direction-selective ganglion cells, Presumably these responses were generated by the alternative pathway involving rod-cone junctions, This APE-resistant pathway may carry the major rod input to Off-center sluggish and On-Off direction-selective ganglion cells.