Schmid S, Guenther E
Department of Pathophysiology of Vision and Neuro-Ophthalmology, University Eye Hospital, Tübingen, Germany.
Neuroreport. 1996 Jan 31;7(2):677-81. doi: 10.1097/00001756-199601310-00070.
The developmental regulation of voltage-gated Na+ and Ca2+ current expression was investigated in rat retinal ganglion cells (RGCs) using whole cell patch clamp recordings. Experiments were performed on retinal whole mounts and slices from embryonic day 14 (E14), the developmental stage where RGCs start to differentiate from their precursor cells, to postnatal day 25 (P25) where the retina is fully differentiated and the animals have opened their eyes. No voltage-activated ion currents could be detected earlier than E17. From E17/18 on, small voltage-gated Na+ and Ca2+ currents could be measured which increased remarkably in amplitude until P16. Analysis of current kinetics and application of specific calcium channel antagonists revealed an alteration in the contribution of different Ca2+ current components to the voltage-activated whole cell Ca2+ current in RGCs during development.
利用全细胞膜片钳记录技术，研究了大鼠视网膜神经节细胞（RGCs）中电压门控性Na⁺和Ca²⁺电流表达的发育调控。实验在胚胎第14天（E14）至出生后第25天（P25）的视网膜全层铺片和切片上进行，E14是RGCs开始从其前体细胞分化的发育阶段，P25时视网膜已完全分化且动物已睁眼。在E17之前未检测到电压激活离子电流。从E17/18开始，可以测量到小的电压门控性Na⁺和Ca²⁺电流，其幅度在P16之前显著增加。对电流动力学的分析以及特异性钙通道拮抗剂的应用表明，在发育过程中，不同Ca²⁺电流成分对RGCs中电压激活的全细胞Ca²⁺电流的贡献发生了改变。
