AN IMPROVED METHOD TO CALCULATE ADIPOSE-TISSUE INTERSTITIAL SUBSTRATERECOVERY FOR MICRODIALYSIS STUDIES

We simultaneously compared the conventional, time-consuming point of n o net flux method for calculation of interstitial substrate recovery n ecessary for in vivo microdialysis studies with a simple isotopic meth od using rat epididymal fat pads. The recovery (%) calculated with the conventional method and the isotopic method for glucose (7.4 +/- 1.1 vs. 6.6 +/- 0.6), glycerol (23 +/- 4 vs. 26 +/- 5) and lactate (40 +/- 8 vs. 38 +/- 5), respectively, were not significantly different. More over, the overall correlation coefficient (N = 25) between the methods was 0.87, p < 0.001. We therefore conclude that the methods yield com parable results, and the more convenient isotopic method should become the method of choice for determining adipose tissue interstitial reco very for glucose, lactate and glycerol.