胰腺β细胞在胰岛素分泌中的循环ADP-ribose
S Takasawa1, K Nata, H Yonekura
1Department of Biochemistry, Tohoku University School of Medicine, Miyagi, Japan.
概括
循环腺二酸二糖 (cADP-ribose),而不是IP3,触发胰腺小岛中的释放. 葡萄糖刺激cADP-ribose的产生,通过动员调解胰岛素分泌.
科学领域:
- 内分泌学 在内分泌学.
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
背景情况:
- 伊诺西1,4,5-三酸盐 (IP3) 传统上被认为是细胞内释放的关键第二信使.
- 调节胰腺小岛中的动员的精确机制对于胰岛素分泌至关重要,需要进一步阐明.
研究的目的:
- 为了研究循环腺二酸 (cADP-ribose) 作为胰腺小岛信号传递中的第二信使的作用.
- 为了确定cADP-ribose,而不是IP3,调解葡萄糖刺激的释放和胰岛素分泌.
主要方法:
- 利用无细胞系统与小岛微小体来评估释放.
- 采用了素透的小岛来研究胰岛素分泌.
- 分析了岛屿提取物,葡萄糖刺激和cADP-ribose在调动中的相互作用.
主要成果:
- 循环腺二酸盐-核糖 (cADP-核糖),尼古丁胺胺氨基二核酸 (NAD +) 的代谢物,诱导了岛屿微观体的释放,而IP3没有.
- 在透的小岛中,cADP-ribose和,但不是IP3,刺激了胰岛素分泌.
- 完整的小岛的葡萄糖刺激导致产生了一种提取物,该提取物诱导小岛微粒体的释放,这种释放由cADP-ribose调节.
结论:
- 循环腺二酸二 (cADP-ribose) 作为胰腺小岛微小体释放的重要调解剂.
- 葡萄糖刺激似乎在小岛内产生cADP-ribose,将其定位为动员和随后的胰岛素分泌的关键第二信使.
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