Metabolite and Ion Fluxes and Ion Channels in Brown and White Adipocytes

Determination of the flux of substances (ions or metabolites) into or out of cells is a recurrent issue in cell biology. This demands the incubation of cells in a medium followed by separation of the cells from this medium. To perform this type of experiment in brown, and especially in white, adipocytes, is challenging, in that the intracellular water volume into which the metabolites/ions are transferred (or from which they are transferred) is small in comparison to total cell volume (because of the lipid droplets). Further, routine techniques to isolate cells from media, i.e., normal centrifugation, cannot be used, because adipocytes will float instead of sink, and will be found in a diffuse band at the top of the vial after centrifugation.