通过NAADP协调激素诱导的Ca2+信号模式在胰腺细胞中
J M Cancela1, G C Churchill, A Galione
1Department of Pharmacology, University of Oxford, UK. j.m.cancela@liverpool.ac.uk
Nature
|March 17, 1999
概括
尼古丁酸腺因二核酸 (NAADP) 触发胰腺细胞中的各种信号,与其他信使不同. 这表明NAADP在哺乳动物中充当了一种新的细胞内信使.
科学领域:
- 细胞生物学 细胞生物学
- 生物化学 生物化学
- 生理学 生理学 生理学
背景情况:
- 激素和神经递质调节细胞内 (Ca2+) 的释放,创建特定的信号模式.
- 伊诺西三酸盐 (InsP3) 和循环氨酸5'-二酸盐-核糖 (cADPR) 是已知的Ca2+信使,分别激活InsP3和氨酸受体.
- 现有的信使并不能完全解释胰腺突细胞中胆囊托基宁 (CCK) 诱导的Ca2+信号复杂性.
研究的目的:
- 研究尼古丁酸腺因二核酸 (NAADP) 作为胰腺细胞中潜在的Ca2+信使的作用.
- 将NAADP的Ca2+调动效应与InsP3和cADPR进行比较.
- 阐明CCK引起的Ca2+信号受调节的机制.
主要方法:
- 测量胰腺状细胞中的细胞内Ca2+度.
- 应用NAADP,cADPR和InsP3来刺激Ca2+的释放.
- 通过使用不同度的NAADP来选择性失活CCK引起的Ca2+信号.
主要成果:
- NAADP触发了各种Ca2+反应,包括短时间和长时间的尖峰,与InsP3和cADPR不同.
- 与cADPR或InsP3.3相比,胰腺酸性细胞对NAADP表现出更高的敏感性.
- 较高的NAADP度可以选择性地抑制CCK诱导的Ca2+信号传递.
结论:
- 在胰腺细胞中,NAADP作为一种强大的Ca2+调动信使.
- 通过NAADP介导的信号与InsP3和cADPR通路不同,并且可以调节它们.
- NAADP代表了一种新的细胞内信使,可能参与哺乳动物细胞信号传递.
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