Angiotensin II: breathtaking in the renal medulla.

Angiotensin II (Ang II) is a major contributor to the progression of renal fibrosis. Wang and colleagues provide evidence that signaling through the prolyl-4-hydroxylase domain (PHD)-hypoxia-inducible factor-1 (HIF-1) pathway mediates profibrotic effects of Ang II in rat renal medullary interstitial cells under normoxic conditions, thus placing the HIF oxygen-sensing pathway into the center of an Ang II-induced profibrotic signaling cascade.