一个G蛋白的激活促进了对通道连接体的激素反应
1Department of Pharmacology, St George's Hospital Medical School, London, UK.
Nature
|December 24, 1987
概括
关氨酸核酸结合 (G) 蛋白调节通道活性. 活性G蛋白增强通道电流,增强连接体相互作用并影响细胞反应.
科学领域:
- 神经科学是一个神经科学.
- 分子生物学分子生物学
- 药理学 药理学是指药理学的学科.
背景情况:
- 关氨酸核酸结合 (G) 蛋白的激活对于受体介导的电压激活通道的抑制至关重要.
- GTP类似物增强受体激动剂,并抑制背部根结节神经元 (DRG) 中的电流.
- 一个持续的L型通道电流组件对瓜诺辛5'-O-3-thiotriphosphate (GTP-gamma-S) 的抑制具有抗性.
研究的目的:
- 为了研究通道抗剂和GTP-gamma-S-修饰电流之间的相互作用.
- 探索激活G蛋白对通道连接体相互作用的影响.
- 为了提供对关氨酸核酸对通道连接体细胞反应的影响的电生理学证据.
主要方法:
- 培养DRG神经元中的通道电流的电生理记录.
- 使用GTP类似物和通道抗剂 (D600,尼菲迪平,迪尔提亚泽姆).
- 对咳毒素对GTP-gamma-S修饰电流的影响的评估.
主要成果:
- 通道对抗剂在内部GTP-gamma-S.S.的存在下显著增强通道电流.
- 这种增强被百日咳毒素取消,表明G蛋白参与 (Gi/Go).
- 激活的G蛋白与通道相互作用,增强连接体的作用.
结论:
- 激活的G蛋白可以与通道相互作用,增强通道连接体的作用.
- 这种相互作用增强了静止状态通道上的激素体位的连接.
- 证明了第一个对关氨酸核酸影响细胞对通道连接体反应的电生理学证据.
相关概念视频
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