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This study suggests an approach for the comparison and evaluation of particular compartments with modest experimental setup costs. A glucose level prediction model was used to evaluate the compartment's glucose transport rate across the blood capillary membrane and the glucose utilization rate by the cells. The glucose levels of the blood, subcutaneous tissue, skeletal muscle tissue, and visceral fat were obtained in experiments conducted on hereditary hypertriglyceridemic rats. After the blood glucose level had undergone a rapid change, the experimenter attempted to reach a steady blood glucose level by manually correcting the glucose infusion rate and maintaining a constant insulin infusion rate. The interstitial fluid glucose levels of subcutaneous tissue, skeletal muscle tissue, and visceral fat were evaluated to determine the reaction delay compared with the change in the blood glucose level, the interstitial fluid glucose level predictability, the blood capillary permeability, the effect of the concentration gradient, and the glucose utilization rate. Based on these data, the glucose transport rate across the capillary membrane and the utilization rate in a particular tissue were determined. The rates obtained were successfully verified against positron emission tomography experiments. The subcuta-neous tissue exhibits the lowest and the most predictable glucose utilization rate, whereas the skeletal muscle tissue has the greatest glucose utilization rate. In contrast, the visceral fat is the least predictable and has the shortest reaction delay compared with the change in the blood glucose level. The reaction delays obtained for the subcutaneous tissue and skeletal muscle tissue were found to be approximately equal using a metric based on the time required to reach half of the increase in the interstitial fluid glucose level. [ABSTRACT FROM AUTHOR]

Abstract: The pancreas, liver and hypothalamus have a regulatory function in the glucose homeostasis. As the blood glucose level changes, these compartments react and the level changes again. Subsequently to this reaction, the interstitial glucose level changes with some delay. In this paper, I propose a hypothesis that the change of the blood glucose level includes information about the estimated rate with which the hypothalamus expects the blood glucose level to return to normal range, by means of regulatory mechanisms of glucose homeostasis. As the interstitial glucose level change reflects the blood glucose level change, I propose a method to estimate the blood-to-interstitial glucose level delay. It is an important factor for glucose level prediction. Once the delay was calculated, it was possible to relate the present blood glucose level and future interstitial glucose level with such coefficients, which do not seem to change over the time of the experiment to a significant extent. Perhaps, it is a parameterization of regulatory processes of glucose homeostasis, which could be possibly encoded within hypothalamus set-points. The delays were constant per subject and ranged from 7min up to 34min for hereditary hypertriglyceridemic rats of 230–480g weight, in experiments with a variable glucose infusion rate. [Copyright &y& Elsevier]