Faculty Collaboration Database

Effect of exposure to hypoxia from birth on aldosterone in rabbits: role of unesterified fatty acids. Am J Physiol 1997 Apr;272(4 Pt 2):R1084-7

Date

04/01/1997

Pubmed ID

9140005

DOI

10.1152/ajpregu.1997.272.4.R1084

Scopus ID

2-s2.0-0030991909   8 Citations

Abstract

Hypoxia and fluid and electrolyte disturbances are serious risks to normal postnatal development. Because a decrease in inspired O2 (hypoxic hypoxia) inhibits aldosterone synthesis in the adult and aldosterone controls water and electrolyte balance, we studied adrenocortical function in rabbits exposed to normobaric normoxia or hypoxic hypoxia (fraction of inspired O2 0.09) from birth. At 21 days of age, rabbits were anesthetized, the adrenals were rapidly removed, and the adrenal capsules containing mostly zona glomerulosa cells were separated. Cells were dispersed with collagenase and studied in vitro. Hypoxia in vivo resulted in a 73% decrease in basal aldosterone release and a 86% decrease in adenosine 3',5'-cyclic monophosphate-stimulated aldosterone release in vitro. We hypothesized that increased unesterified fatty acids could be partly responsible for inhibition of aldosterone synthesis. Total serum unesterified fatty acids in hypoxic kits were significantly increased (298 +/- 14 micromol/l) compared with normoxic kits (184 +/- 31 micromol/l). When cells from hypoxic rabbits were washed with fatty acid-free albumin and studied under conditions devoid of fatty acids, aldosterone production was partially restored. Corticosterone production was not affected by washing. Washing had no effect on aldosterone synthesis by cells from normoxic rats. Finally, exposing washed zona glomerulosa cells to oleic acid (10-50 microM) inhibited aldosteronogenesis. We conclude that exposure to hypoxia from birth attenuates aldosterone production in part due to an increase in levels of unesterified fatty acid levels.

Author List

Raff H, Jankowski BM, Goodfriend TL, Baker JE, Papanek PE

Authors

John E. Baker PhD Professor in the Surgery department at Medical College of Wisconsin
Paula Papanek PhD, MPT, LAT, FACSM Associate Professor & Director of Exercise Science in the Exercise Science & Physical Therapy department at Marquette University
Hershel Raff PhD Professor in the Medicine department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Aging
Aldosterone
Animals
Animals, Newborn
Bucladesine
Cells, Cultured
Corticosterone
Cyclic AMP
Fatty Acids, Nonesterified
Hypoxia
Kinetics
Oleic Acid
Rabbits
Rats
Reference Values
Zona Glomerulosa