移除Ca2+通道β3亚单元可以增强Ca2+振荡频率和胰岛素外细胞形成
Per-Olof Berggren1, Shao-Nian Yang, Manabu Murakami
1The Rolf Luft Center for Diabetes Research, Department of Molecular Medicine, Karolinska Institutet, Karolinska University Hospital Solna, S-17176 Stockholm, Sweden. per-olof.berggren@molmed.ki.se
Cell
|October 14, 2004
概括
β3亚单元对葡萄糖诱导的胰岛素分泌进行负面调节. 通过增加振荡和胰岛素释放,在小鼠中去除这种子单元可以改善葡萄糖平衡,这表明了新的糖尿病治疗点.
科学领域:
- 内分泌学 在内分泌学.
- 分子生物学分子生物学
- 细胞生理学 细胞生理学
背景情况:
- 胰腺β细胞通过胰岛素分泌来调节血糖.
- 葡萄糖通过细胞内 ([Ca2+]i) 的振荡性增加刺激胰岛素的释放.
- 在这些振荡中,电压关闭的Ca2+通道子单元在这些振荡中的确切作用尚未完全理解.
研究的目的:
- 研究电压 Ca2+通道的β3子单元在调节胰腺β细胞中的[Ca2+]i振荡和胰岛素分泌中的功能.
- 为了确定β3亚单元缺乏对葡萄糖平衡和胰岛素分泌的影响.
主要方法:
- 使用了缺乏β3亚单元 (淘汰赛) 的小鼠及其相应的β细胞.
- 测量葡萄糖诱导的[Ca2+]i振荡和胰岛素分泌.
- 在淘汰赛中评估葡萄糖平衡与野生类型小鼠.
主要成果:
- 与野生类型对照相比,Beta3亚单元淘汰的小鼠表现出改善的葡萄糖平衡.
- 缺少β3亚单元导致β细胞中葡萄糖诱导的[Ca2+]i振荡的频率增加.
- 这与增强的内醇1,4,5-三酸盐 (InsP3) 形成和增加细胞内Ca2+调动有关.
- 在β3缺乏细胞中的高葡萄糖度下,胰岛素的释放显著增加.
- 没有观察到β3缺乏对电压式L型Ca2+通道的影响.
结论:
- β3亚单元负调节InsP3诱导的Ca2+释放,从而调节胰腺β细胞中[Ca2+]i振荡的频率.
- 针对β细胞中的β3亚单元,可能为治疗糖尿病提供一种新的治疗策略,特别是在高血糖水平的情况下.
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