Английская Википедия:Estrone glucuronide

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Estrone glucuronide, or estrone-3-D-glucuronide, is a conjugated metabolite of estrone.[1] It is formed from estrone in the liver by UDP-glucuronyltransferase via attachment of glucuronic acid and is eventually excreted in the urine by the kidneys.[1] It has much higher water solubility than does estrone.[1] Glucuronides are the most abundant estrogen conjugates and estrone glucuronide is the dominant metabolite of estradiol.[1]

When exogenous estradiol is administered orally, it is subject to extensive first-pass metabolism (95%) in the intestines and liver.[2][3] A single administered dose of estradiol is absorbed 15% as estrone, 25% as estrone sulfate, 25% as estradiol glucuronide, and 25% as estrone glucuronide.[2] Formation of estrogen glucuronide conjugates is particularly important with oral estradiol as the percentage of estrogen glucuronide conjugates in circulation is much higher with oral ingestion than with parenteral estradiol.[2] Estrone glucuronide can be reconverted back into estradiol, and a large circulating pool of estrogen glucuronide and sulfate conjugates serves as a long-lasting reservoir of estradiol that effectively extends its terminal half-life of oral estradiol.[2][3] In demonstration of the importance of first-pass metabolism and the estrogen conjugate reservoir in the pharmacokinetics of estradiol,[2] the terminal half-life of oral estradiol is 13 to 20 hours[4] whereas with intravenous injection its terminal half-life is only about 1 to 2 hours.[5]

Шаблон:Affinities and estrogenic potencies of estrogen esters and ethers at the estrogen receptors

Шаблон:Estradiol metabolism

See also

References

Шаблон:Reflist

External links

Шаблон:Steroid hormones Шаблон:Estrogen receptor modulators