Erythropoietin concentrations during 10 days of normobaric hypoxia under controlled environmental circumstances.
Serum erythropoietin levels (s-[epo]), haemoglobin concentration ([Hb]), haematocrit (hct), and ferritin concentration ([fer]) were measured in seven healthy male volunteers (20-23 years) exposed continuously to hypoxia (PO(2) 14 kPa) for 10 days. Serum erythropoietin concentration increased significantly from 9.5 +/- 3.51 to 33.6 +/- 11.64 U L(-1) (P < 0.05) after 2 days of hypoxia. Thereafter, s-[epo] decreased. However, after 10 days s-[epo] was 18.7 +/- 5.83 U L(-1) which was still increased above the pre-hypoxia level (P < 0.05). Serum haemoglobin concentration and hct increased over the 10 days of hypoxia, [Hb] from 152 +/- 8.9 to 168 +/- 9.2 gL(-1) (P < 0.001), and hct from 43 +/- 2.4 to 49 +/- 2.6% (P < 0.001). Ferritin concentration decreased significantly during the hypoxic exposure from 82 +/- 46.9 to 44 +/- 31.7 mmol L(-1) after 10 days (P < 0.01). In conclusion, the initial increase of s-[epo] under controlled normobaric hypoxia was marked, 353%, and levelled off after 5-10 days at 62-97% above normoxia level. There was also a significant increase in [Hb] and hct and a decrease in [fer] after 10 days of exposure to normobaric hypoxia.
Berglund
B
B
Division of Medicine, Karolinska Hospital, Stockholm, Sweden.
Gennser
M
M
Ornhagen
H
H
Ostberg
C
C
Wide
L
L
D000222:Adaptation, Physiological; D000328:Adult; D002245:Carbon Dioxide / Q000097:blood; D004921:Erythropoietin / Q000097:blood*; D015444:Exercise / Q000502:physiology*; D006801:Humans; D000860:Hypoxia / Q000097:blood*; D008297:Male; D010100:Oxygen / Q000097:blood; D012129:Respiratory Function Tests; D013997:Time Factors
D004921:Erythropoietin; D002245:Carbon Dioxide; D010100:Oxygen