Decreased binding capacity for alpha-human atrial natriuretic peptide in aldosterone-producing adrenocortical adenoma.
The previous study demonstrated that the aldosterone secretion of aldosterone-producing adrenocortical adenoma failed to be suppressed by human atrial natriuretic peptide, based on the data in synthetic alpha-human atrial natriuretic peptide infusion in vivo and the effect on in vitro secretion from cultured adenoma cells. Using the membrane fractions prepared from human adrenal tissues and an aldosterone-producing adenoma tissues, we characterized the binding sites for [125I] alpha-human atrial natriuretic peptide by the binding study and affinity-labeling of [125I] alpha-human atrial natriuretic peptide. Both normal adrenal and adenoma tissue membrane fractions possessed specific binding sites, however the relative binding capacity for [125I] alpha-human atrial natriuretic peptide in the adenoma preparations was markedly lower than that in the normal adrenal tissue preparation. The specific binding sites for [125I] alpha-human atrial natriuretic peptide were detected at the region of 140 KD and 67-70 KD only in the normal adrenal membrane fractions. Our data suggest that the refractoriness to the effect of atrial peptide may be due to the reduced receptor sites in aldosterone-producing adenoma cells.
Ohashi
M
M
Third Department of Internal Medicine, Faculty of Medicine, Kyushu University, Fukuoka.
Higuchi
K
K
Hashiguchi
T
T
Takayanagi
R
R
Nawata
H
H
D000236:Adenoma / Q000378:metabolism*; D000306:Adrenal Cortex Neoplasms / Q000378:metabolism*; D000450:Aldosterone / Q000096:biosynthesis; D009320:Atrial Natriuretic Factor / Q000378:metabolism*; D001665:Binding Sites; D006801:Humans; D017461:Receptors, Atrial Natriuretic Factor; D011956:Receptors, Cell Surface / Q000378:metabolism*; D014407:Tumor Cells, Cultured
D011956:Receptors, Cell Surface; D000450:Aldosterone; D009320:Atrial Natriuretic Factor; D017461:Receptors, Atrial Natriuretic Factor