1. Glucose handling by the kidney
Glucose handling by the kidney. (Top) Glucose is taken up across the apical membrane by sodium-glucose symporters and leaves across the basolateral membrane via glucose uniporters (GLUT family). In most of the proximal tubule, the sodium-glucose stoichiometry is 1-for-1 (SGLT-2 isoform). In the late proximal tubule, the stoichiometry is 2-for-1 (SGLT-1 isoform). (Bottom) The rates of filtration, reabsorption, and excretion are plotted as a function of plasma glucose concentration. At a given GFR, the rate of glucose filtration is exactly proportional to the plasma concentration. At normal levels of plasma glucose, this rate is well below the Tm and therefore, all the filtered glucose is reabsorbed and none is excreted. However, as plasma glucose rises into the hyperglycemic range, the Tm is reached and any glucose filtered in excess of the Tm is excreted.
Source: Renal Handling of Organic Solutes, Vander's Renal Physiology, 8e
Citation: Eaton DC, Pooler JP. Vander's Renal Physiology, 8e; 2017 Available at: Accessed: October 25, 2017
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