• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Neurochemistry International: The International Journal for the Rapid Publication of Critical Reviews, Preliminary and Original Research Communications in Neurochemistry >Increase of the intracellular Ca2+ concentration mediated by transport of glutamate into rat hippocampal synaptosomes: characterization of the activated voltage sensitive Ca2+ channels.
【24h】

Increase of the intracellular Ca2+ concentration mediated by transport of glutamate into rat hippocampal synaptosomes: characterization of the activated voltage sensitive Ca2+ channels.

机译：谷氨酸转运到大鼠海马突触体中介导的细胞内Ca2 +浓度增加：激活的电压敏感Ca2 +通道的表征。

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The changes in the intracellular free Ca2+ concentration, [Ca2+]i, mediated by glutamate and D-aspartate into rat hippocampal synaptosomes was studied. Glutamate increased the [Ca2+]i in a dose-dependent manner with an EC50 of 1.87 microM and a maximal increase of 31.5 +/- 0.9 nM. We also observed that stimulation of the synaptosomes with 100 microM alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), 100 microM kainate, or 100 microM D-aspartate increased the synaptosomal [Ca2+]i. The effect of either of these non-NMDA receptor agonists and of D-aspartate was additive, suggesting the activation of two different components (the ionotropic non-NMDA receptors or the glutamate transporters). Stimulation of synaptosomes with 100 microM glutamate increased the [Ca2+]i and prevented the effect of either non-NMDA receptor agonists and the effect of D-aspartate. We also observed that incubation of the synaptosomes with D-aspartate induced the Ca(2+)-independent release of glutamate, possibly through the reversal of the glutamate carrier. The aim of incubating the synaptosomes with D-aspartate was to avoid undesirable secondary activation of glutamate receptors. After incubating the synaptosomes with 100 microM D-aspartate (10 min at 37 degrees C), the subsequent stimulation with D-aspartate increased the [Ca2+]i due to glutamate transport. This increase in [Ca2+]i induced by 100 microM D-aspartate was insensitive to 1 microM nitrendipine, but was inhibited by about 50% by the presence of both 500 nM omega-CgTx GVIA and 100 nM omega-Aga IVA or by 500 nM omega-CgTx MVIIC. We clearly identified two different processes by which glutamate increased the [Ca2+]i in rat hippocampal synaptosomes: activation of non-NMDA receptors and activation of the glutamate transporters. We also characterized the voltage sensitive Ca2+ channels (VSCC) activated as a consequence of the glutamate transport, and determined that class B (N-type) and class A (P or Q-type) Ca2+ channels were responsible for about 50% of the signal.
机译：研究了谷氨酸和D-天冬氨酸介导的大鼠海马突触体中细胞内游离Ca2 +浓度[Ca2 +] i的变化。谷氨酸以剂量依赖的方式增加[Ca2 +] i，EC50为1.87 microM，最大增加为31.5 +/- 0.9 nM。我们还观察到用100 microMα-氨基-3-羟基-5-羟基-5-甲基-4-异恶唑丙酸（AMPA），100 microM海藻酸盐或100 microM D-天冬氨酸刺激突触体会增加突触体[Ca2 +] i。这些非NMDA受体激动剂和D-天冬氨酸的作用是累加的，表明两种不同组分（离子型非NMDA受体或谷氨酸转运蛋白）的激活。用100 microM谷氨酸刺激突触小体可增加[Ca2 +] i，并阻止非NMDA受体激动剂和D-天冬氨酸的作用。我们还观察到与D-天门冬氨酸的突触体的孵育诱导了谷氨酸的Ca（2+）独立释放，可能是通过谷氨酸载体的逆转。用D-天冬氨酸孵育突触体的目的是避免不希望的谷氨酸受体的二次激活。将突触小体与100 microM D-天冬氨酸孵育（在37摄氏度下10分钟）后，随后的D-天冬氨酸刺激会由于谷氨酸转运而增加[Ca2 +] i。 100 microM D-天门冬氨酸诱导的[Ca2 +] i的增加对1 microM尼群地平不敏感，但同时存在500 nM omega-CgTx GVIA和100​​ nM omega-Aga IVA或500 nM抑制了约50％ ω-CgTxMVIIC。我们清楚地确定了谷氨酸增加大鼠海马突触小体中[Ca2 +] i的两个不同过程：非NMDA受体的激活和谷氨酸转运蛋白的激活。我们还对由于谷氨酸转运而激活的电压敏感Ca2 +通道（VSCC）进行了表征，并确定B类（N型）和A类（P或Q型）Ca2 +通道占了大约50％。信号。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号