Aldosterone ELISA

Aldosterone is a steroid hormone produced by the
adrenal cortex in the adrenal gland, is the most potent
mineralocorticoid in humans, it regulate sodium and
potassium balance in the blood. Aldosterone secretion appears to be stimulated
primarily through the renin-angiotensin system. Acting on mineralocorticoid receptors (MR) on
principal cells in the collecting ducts of the kidneys, it
increases the permeability of their apical (luminal)
membrane to potassium and sodium and activates
their basolateral Na+/K+ pumps, stimulating ATP
hydrolysis, reabsorbing sodium (Na+) ions and water
into the blood, and excreting potassium (K+) ions into
the urine. Aldosterone regulate plasma bicarbonate
(HCO3-) levels and its acid/base balance.
Aldosterone is responsible for the reabsorption of
about 2% of filtered sodium in the kidneys.
Plasma aldosterone levels normally vary with body
position (uprightsupine) and salt intake. Overall
plasma aldosterone levels show a circadian rhythm
which is similar to but less marked than cortisol, with
peak levels in the early morning; about 75% of the
daily production is secreted between 04:00 am and
10:00 am each day. Age-related levels tend to decline
from fetal through adult life.
Abnormally high plasma aldosterone concentrations
can occur in adenomas, glucocorticoid-responsive
hyperaldosteronism, idiopathic.
Abnormally low aldosterone secretion occurs in a
number of conditions including salt-wasting forms of
congenital adrenal hyperplasia, nephropathy, and
renal tubular acidosis.