ADIPOSE-TISSUE METABOLISM IN THE POSTPRANDIAL PERIOD - MICRODIALYSIS AND ARTERIOVENOUS TECHNIQUES COMPARED

We investigated whether two different methods of studying metabolism i n adipose tissue, microdialysis and the arteriovenous technique, produ ced comparable results during the postprandial period. Interstitial gl ycerol concentrations measured by microdialysis are usually used as an index of intracellular lipolysis, and it is not known whether they al so reflect the intravascular action of lipoprotein lipase in the postp randial period. The two techniques were compared in 10 healthy subject s fed mixed meals. Interstitial glycerol concentrations reflected thos e measured in adipose tissue venous plasma. However, the calculation o f the rate of glycerol release from adipose tissue using the microdial ysis data differed systematically from that using arteriovenous differ ence measurement. The former method gave, on average, 40% lower values than the latter one. The difference is probably due to the assumption s that had to be made for the calculation of glycerol release. The two techniques have complementary places in the study of postprandial adi pose tissue metabolism, with microdialysis reflecting intracellular ho rmone-sensitive lipase action rather than intravascular lipoprotein li pase.