TY - JOUR
T1 - Separation of the glucose-stimulated cytoplasmic and mitochondrial NAD(P)H responses in pancreatic islet β cells
AU - Patterson, George H.
AU - Knobel, Susan M.
AU - Arkhammar, Per
AU - Thastrup, Ole
AU - Piston, David W.
PY - 2000/5/9
Y1 - 2000/5/9
N2 - 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 ≃30 μM. 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 ≃7 μM. Likewise, the NAD(P)H increase of the mitochondrial domain is ≃60 μM and is delayed with respect to the change in cytoplasmic NAD(P)H by ≃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.
AB - 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 ≃30 μM. 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 ≃7 μM. Likewise, the NAD(P)H increase of the mitochondrial domain is ≃60 μM and is delayed with respect to the change in cytoplasmic NAD(P)H by ≃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.
UR - http://www.scopus.com/inward/record.url?scp=0034624997&partnerID=8YFLogxK
U2 - 10.1073/pnas.090098797
DO - 10.1073/pnas.090098797
M3 - Article
C2 - 10792038
AN - SCOPUS:0034624997
SN - 0027-8424
VL - 97
SP - 5203
EP - 5207
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 10
ER -