Fig. 4.

Glucose transport along the proximal tubule of the male (blue) and female (red) rat kidney at differing hyperglycemic levels ([G]). A: tubular glucose flow at selected [G]. B: fractional glucose reabsorption as a function of [G]. Glucosuria occurs at similar hyperglycemic level for male and female rats. C: proximal tubular Na⁺ outflow as a function of [G]. D: proximal tubular water outflow as a function of [G]. As [G] increases, fractional reabsorption of both Na⁺ and water decreases. PCT, proximal convoluted tubule.