a. Excretion of PAH is the sum of filtration across the glomerular capillaries plus secretion from peritubular capillary blood into urine.
b. The curve for excretion is steepest at low plasma PAH concentrations (lower than Tm). Once the Tm for secretion is exceeded and all of the carriers for secretion are saturated, the excretion curve flattens and becomes parallel to the curve for filtration.
c. RPF is measured by the clearance of PAH at plasma concentrations of PAH that are lower than Tm.
Was this article helpful?