Search results
Results from the WOW.Com Content Network
Aldosterone synthase, also called steroid 18-hydroxylase, corticosterone 18-monooxygenase or P450C18, is a steroid hydroxylase cytochrome P450 enzyme involved in the biosynthesis of the mineralocorticoid aldosterone and other steroids. The enzyme catalyzes sequential hydroxylations of the steroid angular methyl group at C18 after initial 11β ...
In individuals with GRA, there is unequal crossing over so that the 5' regulatory region of the 11-hydroxylase gene is fused to the coding region of the aldosterone synthase. [citation needed] The product of this hybrid gene is aldosterone synthase that is ACTH-sensitive [2] in the zona fasciculata of the adrenal gland. [3]
These enzymes are nearly identical (they share 11β-hydroxylation and 18-hydroxylation functions), but aldosterone synthase is also able to perform an 18-oxidation. Moreover, aldosterone synthase is found within the zona glomerulosa at the outer edge of the adrenal cortex; 11β-hydroxylase is found in the zona glomerulosa and zona fasciculata.
18-Hydroxylase (aldosterone synthase) – mineralocorticoid synthesis; 21-Hydroxylase – corticosteroid synthesis; Cytochrome P450 (CYP1, 2, 3) – estrogen metabolism; Hydroxysteroid dehydrogenases (and ketosteroid reductases) 3α-Hydroxysteroid dehydrogenase – androgen, progestogen, and neurosteroid synthesis and metabolism
The outermost layer, the zona glomerulosa is the main site for the production of aldosterone, a mineralocorticoid. The synthesis and secretion of aldosterone are mainly regulated by the renin–angiotensin–aldosterone system. The zona glomerulosa cells express a specific enzyme aldosterone synthase (also known as CYP11B2).
Rather, both renin and aldosterone are measured, and a resultant aldosterone-to-renin ratio (ARR) is used for case detection. [20] [21] A high aldosterone-to-renin ratio suggests the presence of primary hyperaldosteronism. The diagnosis is made by performing a saline suppression test, ambulatory salt loading test, or fludrocortisone suppression ...
Familial hyperaldosteronism is a group of inherited conditions in which the adrenal glands, which are small glands located on top of each kidney, produce too much of the hormone aldosterone. [1] Excess aldosterone causes the kidneys to retain more salt than normal, which in turn increases the body's fluid levels and causes high blood pressure. [1]
It may be increased in 17α-hydroxylase deficiency, [4] in aldosterone synthase deficiency, [5] in primary aldosteronism, and may also indicate a histologic variant of the aldosteronoma. [4] Excessive secretion of 18-OH-DOC can cause mineralocorticoid excess syndrome, although these cases are very rare.