title: Increases in plasma levels of atrial and brain natriuretic peptides after running a marathon: are their effects partly counterbalanced by adrenocortical steroids?
abstract: OBJECTIVE
  Long-distance running results in considerable stress. Little evidence exists about the role of the atrial and brain natriuretic peptides, ANP and BNP, deriving from the myocardium. The aim of our study was to investigate the influence of running 42.195 km on changes in circulating natriuretic propeptides and adrenocortical steroids.
  
  
  METHODS
  We studied 17 male and 2 female runners (age: 28-62 Years) participating in a marathon. Blood samples were obtained before and immediately after the competition. proANP(1-98) and proANP(1-30) as well as Nt-proBNP(8-29) were determined by enzyme immunoassays.
  
  
  RESULTS
  Runners finished the competition between 2 h 58 min and 4 h 25 min. We observed a more pronounced increase in proANP(1-98) (+58%) and proANP(1-30) (+99%, both P<0.001) compared with Nt-proBNP(8-29) (+6%; P=0.005). Increases in proANP(1-30) positively correlated with runners' age (r=0.53; P=0.02). We also observed a marked increase in cortisol (+73%) and especially in aldosterone (+431%, both P<0.001).
  
  
  CONCLUSIONS
  Cardiac strain during long-distance running may explain the pronounced increase in proANP. Other explanations for the observed rise in plasma levels might be a change in the permeability of myocardial cells and an impaired clearance. A rise in adrenocortical steroids may compensate for the negative influence of ANP on natriuresis and blood pressure. Positive effects of ANP during a marathon could be the regulation of body temperature by influencing sweat glands as well as the stimulation of lipolysis compensating for the enormous energy demand.
authors.affiliation: Division of Cardiology, Department of Internal Medicine II, General University Hospital, Waehringer Guertel 18-20, A-1090 Vienna, Austria. alexander.niessner@univie.ac.at
authors.forename: Alexander
authors.initials: A
authors.lastname: Niessner
authors.forename: Sophie
authors.initials: S
authors.lastname: Ziegler
authors.forename: Jörg
authors.initials: J
authors.lastname: Slany
authors.forename: Elke
authors.initials: E
authors.lastname: Billensteiner
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Woloszczuk
authors.forename: Georg
authors.initials: G
authors.lastname: Geyer
mesh_terms: D000222:Adaptation, Physiological; D000302:Adrenal Cortex / Q000378:metabolism; D000328:Adult; D000450:Aldosterone / Q000097:blood*; D009320:Atrial Natriuretic Factor / Q000097:blood*; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000378:metabolism; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D011498:Protein Precursors / Q000097:blood; D012420:Running / Q000502:physiology*
chemical_list: D011498:Protein Precursors; D020097:Natriuretic Peptide, Brain; D000450:Aldosterone; D009320:Atrial Natriuretic Factor; D006854:Hydrocortisone