What happens to filtered, excreted, & reabsorbed glucose as you increase plasma glucose concentration (Pgluc)?
- • Filtration increase as a linear function of plasma glucose
• Reabsorption: increases linearly up until Pgluc
= 3 mg/mL; at this point it levels off b/c the max reabsorption rate has been reached; transporters in the proximal tubule are saturated, so no more can be reabsorbed → glucose appears in urine
• Excretion: none is excreted when Pgluc
< 2 mg/mL b/c all of it is completely reabsorbed; above 3 mg/mL in plasma, excretion increases linearly