Cover Image


View/Hide Left Panel

TABLE 18-2 Human Studies Detailing Hormonal Alterations During Hypoxia or Ascent or Stay at High Altitudes


Study Details


Acute hypoxia

Heyes et al., 1982

Eleven males, 18–40 yr, tested with hypoxia, with and without hypobaria.

ALDO reduced, prolactin rose. AVP increased only with hypotension. Hypobaria not important except for prolactin.

Okazaki et al., 1984

Eighteen males, two females, 23–48 yr, studied at 6,000 m (19,685 ft) for 3 hours in chamber.

No change at 4,000 m (13,123 ft). At 5,000 m (16,404 ft), PV fell, ALDO and ACTH rose. At 6,000 m, ALDO, PRA, and cortisol increased.

Aschak et al., 1985

Ten males, 18–24 yr, usual diet. 10.5 and 12 percent FIO2. PO2 35–46 mm Hg. Water loading and replacement of urine volume.

No change in ALDO, AVP, PRA, NE, bradykinin. No change in urine volume, urine sodium. AVP increased only when subjects had nausea.

Colice and Ramirez, 1985

Group 1: hypoxia (SAT 90 percent) for 1 hour. Group 2: hypoxia (SAT 90 percent) for 1 hour, (SAT 80 percent) for 1 hour. Studied twice with normal and low-salt diet.

ALDO reduced; PRA and ACE unchanged. No further increase in second hour PRA-ALDO uncoupled. No change in hemodynamics. ALDO reduction significant only when both groups pooled. Diet sodium important in degree of response.

Maresh et al., 1985

Seven low-altitude and seven high-altitude natives (1,830–2,200 m [6,004–7,218 ft]). Tested in hypobaric chamber (447 mm Hg) for 2 days.

ALDO reduced; cortisol increased. High-altitude natives have similar but damped responses. ERPF and heart rate increased.

Hypoxia-high altitude studies; no exercise

Frayser et al., 1975

Nine subjects studied at SL, day 5 at 3,048 m (10,000 ft), days 3 and 7 at 5,334 m (17,500 ft). Eight subjects at SL, day 5 at 2,926 m (9,600 ft), days 5 and 10 at 5,334 m (17,500 ft). Four subjects got acetazolamide before ascent to 5,334 m (17,500 ft).

At 2,744–3,049 m (9,000–10,000 ft), ALDO, PRA unchanged, cortisol rose. At 5,335 m (17,500 ft), PRA and cortisol rose. Normal by day 5.

Olsen et al., 1992

Eight males, 27–42 yr, studied at SL and after 48 hours at 4,350 m (14,272 ft). Measurements at rest and exercise. One-half liter water load.

Increase in NE, fall in ALDO and PRA. Epi and ANP unchanged.

The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement