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Because of the normal aldosterone level, hypertension is not expected. Normal cortisol level can be explained by the strong negative feedback mechanism of cortisol on hypothalamus-pituitary axis system. That is, in the beginning, 17,20-lyase deficiency will block synthesis of sex steroid hormones, forcing the pathways to produce more cortisol.
17α-Hydroxyprogesterone (17α-OHP), also known as 17-OH progesterone (17-OHP), [1] or hydroxyprogesterone (OHP), is an endogenous progestogen steroid hormone related to progesterone. [ 2 ] [ 3 ] [ 4 ] It is also a chemical intermediate in the biosynthesis of many other endogenous steroids, including androgens , estrogens , glucocorticoids ...
Currently, in the United States and over 40 other countries, every child born is screened for 21-hydroxylase CAH at birth. This test detects elevated levels of 17α-hydroxyprogesterone (17-OHP). Detecting high levels of 17-OHP enables early detection of CAH. Newborns detected early enough can be placed on medication and live relatively normal ...
Cortisol levels are lower in CAH subjects, on average, [38] however, in milder cases cortisol levels can be normal, but, this has not been yet well studied. Cortisol measurement using immunoassays is prone to cross-reactivity with various substances including 21-deoxycortisol that raises due to 21-hydroxylase deficiency, leading to falsely high ...
The condition of 21-hydroxylase deficiency is screened by measuring serum levels of 17α-hydroxyprogesterone (17-OHP) in the morning and between day 3 and 5 of the menstrual cycle (for females) to reduce the possibility of false positive results. [12] 17-OHP is used as a marker of the 21-hydroxylase enzyme activity since the 1980s. [52]
More specifically, the enzyme acts upon pregnenolone and progesterone to add a hydroxyl (-OH) group at carbon 17 position (C17) of the steroid D ring (the 17α-hydroxylase activity, EC 1.14.14.19), or acts upon 17α-hydroxyprogesterone and 17α-hydroxypregnenolone to split the side-chain off the steroid nucleus (the 17,20-lyase activity, EC 1 ...
As such 17α-hydroxypregenolone represents an intermediary in the Δ 5 pathway that leads from pregnenolone to DHEA. 17α-Hydroxypregneolone is also converted to 17α-hydroxyprogesterone, a prohormone for glucocorticosteroids and androstenedione through the activity of 3α-hydroxysteroid dehydrogenase.
In individuals with congenital adrenal hyperplasia due to enzyme deficiencies like 21-hydroxylase or cytochrome P450 oxidoreductase deficiency, these pathways can activate at any age with increased levels of precursors like progesterone or 17α-hydroxyprogesterone.