Real-time analysis of glucose metabolism by microscopy

Glucose metabolism has traditionally been assayed via biochemical means. Fl uorescence monitoring of NAD(P)H levels has provided a noninvasive method t o assay glucose metabolism in cells and tissues. However these measurements have traditionally been of low resolution (no subcellular information) bec ause of limitations imposed by optical and cellular photodamage problems. T he recent advent of two-photon excitation microscopy as a dependable tool f or biological research has opened the possibility of real-time, high-resolu tion analysis of glucose metabolism in living cells. Such measurements have the potential to provide subcellular information from intact tissue that c annot be obtained by other techniques.