Faculty Collaboration Database

Oxygen sensitivity of potassium- and angiotensin II-stimulated aldosterone release by bovine adrenal cells. J Endocrinol 1991 Apr;129(1):43-8

Date

04/01/1991

Pubmed ID

2030327

DOI

10.1677/joe.0.1290043

Scopus ID

2-s2.0-0026030089 (requires institutional sign-in at Scopus site)   5 Citations

Abstract

Angiotensin II (AII) and extracellular K+, acting through different intracellular mechanisms, stimulate aldosterone release in a synergistic fashion. We have previously shown that decreases in oxygen (O2) within the physiological range inhibit AII, cyclic AMP (cAMP) and ACTH-stimulated aldosterone release. The present experiment evaluated the effect of various concentrations of O2 on K+-stimulated aldosterone release in the presence and absence of AII. Dispersed bovine adrenal glomerulosa cells were incubated with different concentrations of K+ (0.9-5.4 mmol/l) without and with AII (10 nmol/l) under different concentrations of O2 (0, 5 or 50%); 21% O2 (pO2 = 19.9 +/- 0.5 kPa,n = 9) was used as reference control for comparison. In all cases, increases in K+ stimulated aldosterone release, an effect augmented by AII. Under 0% O2 (pO2 = 8.1 +/- 0.3 kPa, n = 3) and 5% O2 (pO2 = 12.8 +/- 0.5 kPa, n = 3), aldosterone release stimulated by K+ or K+/AII was significantly inhibited compared with that under 21% O2. Conversely, under 50% O2 (pO2 = 36.3 +/- 2.5 kPa, n = 3), aldosterone release stimulated by K+ or K+/AII was significantly augmented. Cortisol secretion was not significantly affected by 5% or 50% O2 but was significantly decreased under 0% O2. The effect of O2 on K+/AII stimulation of aldosterone release, as well as previous experiments with cAMP, progesterone and ACTH, suggest a final common post-receptor oxygen-sensitive component of the aldosterone synthetic pathway. It is suggested that one or more enzymes in the aldosterone synthetic pathway is/are exquisitely sensitive to small changes in O2 within the physiological range.

Author List

Brickner RC, Raff H

Author

Hershel Raff PhD Professor in the Academic Affairs department at Medical College of Wisconsin

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

Adrenal Glands
Aldosterone
Angiotensin II
Animals
Cattle
Cells, Cultured
Oxygen
Potassium
Stimulation, Chemical