PERMEATION OF CALCIUM-IONS THROUGH NON-NMDA GLUTAMATE CHANNELS IN RETINAL BIPOLAR CELLS
PERMEATION OF CALCIUM-IONS THROUGH NON-NMDA GLUTAMATE CHANNELS IN RETINAL BIPOLAR CELLS
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DOI：
10.1126/science.1849316
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发表时间：
1991-03-29
期刊：
影响因子：
56.9
通讯作者：
WILSON, M
中科院分区：
文献类型：
--
作者：
GILBERTSON, TA;SCOBEY, R;WILSON, M
钙离子通过谷氨酸门控通道的传导在长时程增强的诱导中是重要的，并且可能触发其他细胞变化。在缺乏N-甲基-D-天冬氨酸（NMDA）型谷氨酸门控通道的视网膜双极细胞中，检查了通过非NMDA通道的钙渗透性。细胞外钙浓度的变化意外地影响谷氨酸诱导电流的逆转电位，其方式与这些通道对钙具有高度渗透性一致。外部镁离子以电压非依赖性方式促进这些非NMDA通道的脱敏。因此，除了仅传导钠和钾的非NMDA通道外，还有一类也可渗透钙。
The conduction of calcium ions through glutamate-gated channels is important in the induction of long-term potentiation and may trigger other cellular changes. In retinal bipolar cells, which lack the N-methyl-D-aspartate (NMDA) type of glutamate-gated channel, calcium permeability through non-NMDA channels was examined. Changes in extracellular calcium concentration unexpectedly affected the reversal potential for glutamate-induced currents in a manner consistent with these channels being highly permeable to calcium. External magnesium ions promote desensitization of these non-NMDA channels in a voltage-independent way. Thus, in addition to non-NMDA channels that conduct only sodium and potassium, there is a class that is also permeable to calcium.