Separation of the glucose-stimulated cytoplasmic mitochondrial NAD(P)H responses in pancreatic islet β cells
Separation of the glucose-stimulated cytoplasmic mitochondrial NAD(P)H responses in pancreatic islet β cells
复制标题
DOI：
10.1073/pnas.090098797
复制
发表时间：
2000-05-09
影响因子：
11.1
通讯作者：
Piston, DW
中科院分区：
文献类型：
--
作者：
Patterson, GH;Knobel, SM;Piston, DW
使用双光子激发显微镜对葡萄糖刺激下完整胰岛的 NAD(P)H 自发荧光进行成像和量化。在最大葡萄糖刺激下，全细胞 NAD(P)H 水平的上升估计约为 30 μM。然而，由于葡萄糖刺激的胰岛素分泌涉及糖酵解和克雷布循环代谢，因此在细胞外基质上培养胰岛，从而促进细胞扩散并允许对来自细胞质和线粒体的 NAD(P)H 信号进行空间分辨率。研究表明，这两个区室的代谢反应受到不同营养物质应用的不同刺激。细胞质域内 NAD(P)H 荧光的葡萄糖刺激增加估计约为 7 μM。同样，线粒体域的 NAD(P)H 增加约为 60 μM，并且相对于细胞质 NAD(P)H 的变化延迟约 20 秒。因此，葡萄糖刺激的 NAD(P)H 中线粒体的大变化主导了总信号，但可能取决于较小但更快速的细胞质增加。
Two-photon excitation microscopy was used to image and quantify NAD(P)H autofluorescence from intact pancreatic islets under glucose stimulation. At maximal glucose stimulation, the rise in whole-cell NAD(P)H levels was estimated to be approximate to 30 mu M. However, because glucose-stimulated insulin secretion involves both glycolytic and Kreb's cycle metabolism islets were cultured on extracellular matrix that promotes cell spreading and allows spatial resolution of the NAD(P)H signals from the cytoplasm and mitochondria. The metabolic responses in these two compartments are shown to be differentially stimulated by various nutrient applications. The glucose-stimulated increase of NAD(P)H fluorescence within the cytoplasmic domain is estimated to be approximate to 7 mu M. Likewise, the NAD(P)H increase of the mitochondrial domain is approximate to 60 mu M and is delayed with respect to the change in cytoplasmic NAD(P)H by approximate to 20 sec. The large mitochondrial change in glucose-stimulated NAD(P)H thus dominates the total signal but may depend on the smaller but more rapid cytoplasmic increase.