翻訳と辞書 |
Sex hormone-binding globulin
Sex hormone-binding globulin (SHBG) or sex steroid-binding globulin (SSBG) is a glycoprotein that binds to the two sex hormones: androgen and estrogen. Other steroid hormones such as progesterone, cortisol, and other corticosteroids are bound by transcortin. SHBG is found in all vertebrates apart from birds. ==Transport of sex hormones== Testosterone and estradiol circulate in the bloodstream, bound mostly to SHBG and to a lesser extent serum albumin and corticosteroid-binding globulin (CBG) (AKA transcortin). Only a very small fraction of about 1-2% is unbound, or "free," and thus biologically active and able to enter a cell and activate its receptor. SHBG inhibits the function of these hormones. Thus, bioavailability of sex hormones is influenced by the level of SHBG. The relative binding affinity of various sex steroids for SHBG is dihydrotestosterone (DHT) > testosterone > androstenediol > estradiol > estrone. DHEA is weakly bound to SHBG as well, but DHEA-S is not.〔 Androstenedione is not bound to SHBG either, and is instead bound solely to albumin.
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「Sex hormone-binding globulin」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.
|
|