翻訳と辞書
Words near each other
・ "O" Is for Outlaw
・ "O"-Jung.Ban.Hap.
・ "Ode-to-Napoleon" hexachord
・ "Oh Yeah!" Live
・ "Our Contemporary" regional art exhibition (Leningrad, 1975)
・ "P" Is for Peril
・ "Pimpernel" Smith
・ "Polish death camp" controversy
・ "Pro knigi" ("About books")
・ "Prosopa" Greek Television Awards
・ "Pussy Cats" Starring the Walkmen
・ "Q" Is for Quarry
・ "R" Is for Ricochet
・ "R" The King (2016 film)
・ "Rags" Ragland
・ ! (album)
・ ! (disambiguation)
・ !!
・ !!!
・ !!! (album)
・ !!Destroy-Oh-Boy!!
・ !Action Pact!
・ !Arriba! La Pachanga
・ !Hero
・ !Hero (album)
・ !Kung language
・ !Oka Tokat
・ !PAUS3
・ !T.O.O.H.!
・ !Women Art Revolution


Dictionary Lists
翻訳と辞書 辞書検索 [ 開発暫定版 ]
スポンサード リンク

3 beta hydroxysteroid dehydrogenase deficiency : ウィキペディア英語版
Congenital adrenal hyperplasia due to 3 beta-hydroxysteroid dehydrogenase deficiency

3β-Hydroxysteroid dehydrogenase II deficient congenital adrenal hyperplasia (3β-HSD CAH) is an uncommon form of congenital adrenal hyperplasia (CAH) resulting from a mutation in the gene for one of the key enzymes in cortisol synthesis by the adrenal gland, 3β-hydroxysteroid dehydrogenase (3β-HSD) type II (HSD3B2).〔''Congenital Adrenal Hyperplasia'', P Stewart, Chapter 14, Section IV, Williams Textbook of Endocrinology, 11th edition, Elsevier, 2008, p. 485-494.〕 As a result, higher levels of 17OH-pregnenolone appear in the blood with adrenocorticotropic hormone (ACTH) challenge, which stimulates adrenal corticosteroid synthesis.
There is a wide spectrum of clinical presentations of 3β-HSD CAH, from mild to severe forms. The uncommon severe form results from a complete loss of enzymatic activity and manifests itself in infancy as salt wasting due to the loss of mineralocorticoids. Milder forms resulting from incomplete loss of 3β-HSD type II function do not present with adrenal crisis, but can still produce virilization of genetically female infants and undervirilization of genetically male infants. As a result, this form of primary hypoadrenalism is the only form of CAH that can cause ambiguous genitalia in both genetic sexes.
==Pathophysiology==
3β-HSD II mediates three parallel dehydrogenase/isomerase reactions in the adrenals that convert Δ4 to Δ5 steroids: pregnenolone to progesterone, 17-Hydroxypregnenolone to 17-Hydroxyprogesterone, and DHEA to androstenedione. 3β-HSD II also mediates an alternate route of testosterone synthesis from androstenediol in the testes. 3β-HSD deficiency results in large elevations of pregnenolone, 17-hydroxypregnenolone, and DHEA.
However, complexity arises from the presence of a second 3β-HSD (3β-HSD I) coded by a different gene, expressed in the liver and placenta, and unaffected in 3β-HSD deficient CAH. The presence of this second enzyme has two clinical consequences. First, 3β-HSD II can convert enough of the excess 17-hydroxypregnenolone to 17OHP to produce 17OHP levels suggestive of common 21-hydroxylase deficient CAH. Measurement of the other affected steroids distinguishes the two. Second, 3β-HSD I can convert enough DHEA to testosterone to moderately virilize a genetically female fetus.

抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)
ウィキペディアで「Congenital adrenal hyperplasia due to 3 beta-hydroxysteroid dehydrogenase deficiency」の詳細全文を読む



スポンサード リンク
翻訳と辞書 : 翻訳のためのインターネットリソース

Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.