| Item |
Information |
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Drug Groups
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approved; investigational |
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Description
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Generally refers to the 17-beta-isomer of estradiol, an aromatized C18 steroid with hydroxyl group at 3-beta- and 17-beta-position. Estradiol-17-beta is the most potent form of mammalian estrogenic steroids. In humans, it is produced primarily by the cyclic ovaries and the placenta. It is also produced by the adipose tissue of men and postmenopausal women. The 17-alpha-isomer of estradiol binds weakly to estrogen receptors (receptors, estrogen) and exhibits little estrogenic activity in estrogen-responsive tissues. Various isomers can be synthesized. [PubChem] |
| Indication |
For the treatment of urogenital symptoms associated with post-menopausal atrophy of the vagina (such as dryness, burning, pruritus and dyspareunia) and/or the lower urinary tract (urinary urgency and dysuria). |
| Pharmacology |
Estradiol, the principal intracellular human estrogen, is substantially more active than its metabolites, estrone and estriol, at the cellular level. |
| Toxicity |
Can cause nausea and vomiting, and withdrawal bleeding may occur in females. |
| Affected Organisms |
| • |
Humans and other mammals |
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| Biotransformation |
Exogenous estrogens are metabolized using the same mechanism as endogenous estrogens. Estrogens are partially metabolized by cytochrome P450. |
| Absorption |
43% |
| Half Life |
36 hours |
| Protein Binding |
>95% |
| Elimination |
Estradiol, estrone and estriol are excreted in the urine along with glucuronide and sulfate conjugates. |
| References |
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Pentikainen V, Erkkila K, Suomalainen L, Parvinen M, Dunkel L: Estradiol acts as a germ cell survival factor in the human testis in vitro. J Clin Endocrinol Metab. 2000 May;85(5):2057-67.
[Pubmed]
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Sharpe RM, Skakkebaek NE: Are oestrogens involved in falling sperm counts and disorders of the male reproductive tract? Lancet. 1993 May 29;341(8857):1392-5.
[Pubmed]
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Raman JD, Schlegel PN: Aromatase inhibitors for male infertility. J Urol. 2002 Feb;167(2 Pt 1):624-9.
[Pubmed]
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Carani C, Qin K, Simoni M, Faustini-Fustini M, Serpente S, Boyd J, Korach KS, Simpson ER: Effect of testosterone and estradiol in a man with aromatase deficiency. N Engl J Med. 1997 Jul 10;337(2):91-5.
[Pubmed]
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Behl C, Widmann M, Trapp T, Holsboer F: 17-beta estradiol protects neurons from oxidative stress-induced cell death in vitro. Biochem Biophys Res Commun. 1995 Nov 13;216(2):473-82.
[Pubmed]
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Schmidt JW, Wollner D, Curcio J, Riedlinger J, Kim LS: Hormone replacement therapy in menopausal women: Past problems and future possibilities. Gynecol Endocrinol. 2006 Oct;22(10):564-77.
[Pubmed]
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Foresta C, Zuccarello D, Biagioli A, De Toni L, Prana E, Nicoletti V, Ambrosini G, Ferlin A: Oestrogen stimulates endothelial progenitor cells via oestrogen receptor-alpha. Clin Endocrinol (Oxf). 2007 Oct;67(4):520-5. Epub 2007 Jun 15.
[Pubmed]
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Garcia-Segura LM, Sanz A, Mendez P: Cross-talk between IGF-I and estradiol in the brain: focus on neuroprotection. Neuroendocrinology. 2006;84(4):275-9. Epub 2006 Nov 23.
[Pubmed]
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