Gerhard Giebisch, Erich E. Windhager, Peter S. Aronson
The kidney plays a central role in controlling the plasma levels of a wide range of solutes that are present at low concentrations in the body. The renal excretion of a solute depends on three processes—filtration, reabsorption, and secretion (see pp. 732–733). The kidney filters and then totally reabsorbs some of the substances we discuss in this chapter (e.g., glucose). Others, it filters and also secretes (e.g., the organic anion para-aminohippurate [PAH]). Still others, the kidney filters, reabsorbs, and secretes (e.g., urea).