Multiple picrotoxinin effect on glycine channels in rat hippocampal neurons.
Multiple picrotoxinin effect on glycine channels in rat hippocampal neurons.
复制标题
印防己毒素对大鼠海马神经元甘氨酸通道的多重作用。
DOI：
10.1016/s0306-4522(98)00158-4
复制
发表时间：
1998
期刊：
影响因子：
3.3
通讯作者：
Fuse,T
中科院分区：
文献类型：
--
作者：
Yoon,KW;Wotring,VE;Fuse,T
在分离的大鼠海马神经元培养的全细胞和切除的外向补丁中，研究了印防己毒素对甘氨酸诱导的氯电流的影响。印防己毒素阻断甘氨酸诱导的氯电流。20μM印防己毒宁对甘氨酸的剂量反应关系表明存在竞争性机制。然而，在1mM时，印苦毒素的作用在很大程度上是非竞争性的。在切除的补丁，甘氨酸激活两种类型的通道区分电导的差异。第一组的单沟道电导约为47pS，另一组约为100pS。偶尔，两种类型的通道被发现在同一切除补丁。低浓度的印防己毒素选择性阻断大电导通道。在0.5至1mM的较高浓度下，印防己毒素通过闪烁阻断来阻断小电导通道。这些结果表明，大鼠海马神经元的全细胞甘氨酸电流至少由两种类型的通道介导。这两类通道具有不同的电导率、对印防己毒素的敏感性和不同的印防己毒素阻断机制。
The effect of picrotoxinin on glycine-induced chloride currents was studied in dissociated rat hippocampal neuron culture in whole-cell and excised outside-out patches. Picrotoxinin blocked the glycine induced chloride currents. The picrotoxinin effect at 20μM on glycine dose response relationship suggested a competitive mechanism. However, at 1mM, the picrotoxinin effect was largely noncompetitive. In excised patches, glycine activated two types of channels distinguished by a difference in conductances. The first group had single channel conductances of around 47pS and another around 100pS. Occasionally, both types of channels were found in the same excised patch. Low concentration of picrotoxinin selectively blocked large conductance channels. At higher concentrations of 0.5 to 1mM, picrotoxinin blocked the small conductance channels by a flickering block. These findings indicate that the whole-cell glycine current in rat hippocampal neurons is mediated by at least two types of channels. The two types of channels have distinct conductance, picrotoxinin sensitivity and different mechanism of picrotoxinin block.