质细胞的谷氨酸吸收载体对抗转运改变pH的阳离子
M Bouvier1, M Szatkowski, A Amato
1Department of Physiology, University College London, UK.
Nature
|December 3, 1992
概括
质细胞通过运输器调节细胞外谷氨酸水平,该运输器也会移动质子,从而影响神经元活动,并可能通过pH值变化调节神经元-质相互作用.
科学领域:
- 神经科学是一个神经科学.
- 细胞生物学 细胞生物学
- 生物化学 生物化学
背景情况:
- 质细胞在神经递质调节中发挥着至关重要的作用,特别是谷氨酸.
- 质细胞吸收谷氨酸对于维持细胞外谷氨酸度低于神经毒性水平至关重要.
- 谷氨酸吸收载体的离子运输固态度是一个正在进行的辩论的主题.
研究的目的:
- 为了研究质谷氨酸吸收载体的离子运输机制.
- 要确定谷氨酸转运体是否也携带质子或pH值变化的离子.
- 阐明谷氨酸吸收载体的固态度及其对细胞外谷氨酸水平的影响.
主要方法:
- 对与质酸盐在质细胞中吸收相关的离子流的实验性研究.
- 在谷氨酸运输过程中测量细胞外和细胞内pH值的变化.
- 基于观察到的离子运动,分析载体体积测量.
主要成果:
- 谷氨酸吸收载体产生细胞外化和细胞内酸化.
- 载体从质细胞中运输出离子.
- 拟议的载体循环涉及2Na+和1个谷氨酸离子进入细胞的运输,1个K+和1个OH- (或HCO3-) 出.
- 这种固体测量预测了生理和无毒细胞外谷氨酸度.
结论:
- 质谷氨酸转运体积极参与pH调节.
- 谷氨酸载体的OH-/HCO3-运输会影响神经元环境.
- 这种机制可能代表了神经元-质沟通的新途径.
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