Figure 5. The relationship of plasma AVP concentration to urine osmolality. Shaded area represents range of normal; single line indicates representative individual. AVP has additional effects at other sites in the nephron: decreasing medullary blood flow; stimulating active urea transport in the distal collecting duct; and stimulating active sodium transport into the renal interstitium. AVP up-regulates the bumetanide-sensitive sodium-potassium-chloride cotransporter (SLC12A1) in the thick ascending loop of Henle through both a rapid acceleration of post-translational processing/trafficking and an increase in SCLC12A1 gene expression. Together, these contribute to the generation and maintenance of a hypertonic medullary interstitium, and augment AVP-dependent water resorption (16).