title: Angiotensin II infusion increases plasma erythropoietin levels via an angiotensin II type 1 receptor-dependent pathway.
abstract: BACKGROUND
  Angiotensin-converting enzyme inhibitors (ACEIs) have been shown to lower hematocrit and erythropoietin (EPO), but a direct link between angiotensin II (Ang II) and EPO in humans has not been shown.
  
  
  METHODS
  Placebo or Ang II was infused for six hours in nine healthy male volunteers with and without blockade of the Ang II subtype 1 receptor (AT1R). EPO concentrations were measured 3, 6, 12, and 24 hours after the start of the infusion.
  
  
  RESULTS
  Ang II raised the mean arterial pressure by about 20 mm Hg. Consistent with the known diurnal variation, EPO levels rose significantly (P < or = 0.02) during the day in all groups. During Ang II infusion, EPO levels rose to significantly higher levels after 6 and 12 hours compared with placebo [9.9 +/- 3.5 vs. 7.2 +/- 3.1 mU/mL (3 h, P = NS); 16.9 +/- 4.5 vs. 8.8 +/- 3.7 mU/mL (6 h, P = 0.01); 17.0 +/- 8.6 vs. 11.1 +/- 4.7 mU/mL (12 h, P = 0.01)] and returned to baseline after 24 hours (7.9 +/- 3.8 vs. 10.6 +/- 8.6 mU/mL, P = NS). With AT1R blockade, blood pressure remained normal during Ang II infusion, and EPO levels were never significantly different from placebo [6.8 +/- 4.8, 10.5 +/- 5.6, 13.1 +/- 9.0, and 12.4 +/- 10.1 mU/mL at 3, 6, 12, and 24 h after infusion, respectively, P = NS].
  
  
  CONCLUSIONS
  Ang II increases EPO levels in humans. This increase requires the participation of AT1R.
authors: Funktionsbereich Nephrologie, Medizinische Klinik IV, Zentrum der Inneren Medizin, and Abteilung für klinische Pharmakologie, Zentrum der Pharmakologie, J.W. Goethe-Universität, Frankfurt am Main, Germany.
authors: J
authors: J
authors: Gossmann
authors: R
authors: R
authors: Burkhardt
authors: S
authors: S
authors: Harder
authors: T
authors: T
authors: Lenz
authors: A
authors: A
authors: Sedlmeyer
authors: U
authors: U
authors: Klinkhardt
authors: H
authors: H
authors: Geiger
authors: E H
authors: EH
authors: Scheuermann
mesh_terms: D000328:Adult; D000804:Angiotensin II / Q000494:pharmacology*; D001794:Blood Pressure / Q000187:drug effects; D004921:Erythropoietin / Q000097:blood*; D006801:Humans; D008297:Male; D009994:Osmolar Concentration; D044140:Receptor, Angiotensin, Type 1; D044139:Receptor, Angiotensin, Type 2; D011945:Receptors, Angiotensin / Q000502:physiology*; D012016:Reference Values; D013997:Time Factors
chemical_list: D044140:Receptor, Angiotensin, Type 1; D044139:Receptor, Angiotensin, Type 2; D011945:Receptors, Angiotensin; D004921:Erythropoietin; D000804:Angiotensin II