Regulation of the glucose supply from capillary to tissue examined by developing a capillary model

• Published in: The journal of physiological sciences 2018-07, Vol.68 (4), p.355-367
• Main Authors: Maeda, Akitoshi, Himeno, Yukiko, Ikebuchi, Masayuki, Noma, Akinori, Amano, Akira
• Format: Article
• Language: English
• Subjects: Animals; Biological Transport; Blood flow; Capillaries; Capillaries - metabolism; Capillary Permeability - physiology; Convection; Dextrose; Diffusion; Glucose; Glucose - metabolism; Glucose transport; Models, Theoretical; Original Paper; Scaling
• ISSN: 1880-6546; 1880-6562
• DOI: 10.1007/s12576-017-0538-8

A new glucose transport model relying upon diffusion and convection across the capillary membrane was developed, and supplemented with tissue space and lymph flow. The rate of glucose utilization (J ) in the tissue space was described as a saturation function of glucose concentration in the interstitial fluid (C ), and was varied by applying a scaling factor f to J . With f = 0, the glucose diffusion ceased within ~20 min. While, with increasing f, the diffusion was accelerated through a decrease in C , but the convective flux remained close to resting level. When the glucose supplying capacity of the capillary was measured with a criterion of J /J  = 0.5, the capacity increased in proportion to the number of perfused capillaries. A consistent profile of declining C along the capillary axis was observed at the criterion of 0.5 irrespective of the capillary number. Increasing blood flow scarcely improved the supplying capacity.