Pharmacodynamics<unk>  is an estrogen, or an agonist of the estrogen receptors (ERs), the ERα and ERβ. In terms of relative binding affinity for the ERs,<unk>  has about 13% and 49% of that of estradiol for the ERα and ERβ, respectively. Analogously to the reversible transformation of estrone into estradiol by 17β-hydroxysteroid dehydrogenase,<unk>  can be converted into the more potent estrogen 17β-dihydroequilin in the body. This estrogen has about 113% and 108% of the relative binding affinities of estradiol for the ERα and ERβ, respectively.<unk>  is present in CEEs in the form of<unk>  sulfate, which itself is inactive and acts as a prodrug of<unk>  via steroid sulfatase. Similarly to synthetic estrogens like ethinylestradiol,<unk>  and CEEs have disproportionate effects in certain tissues such as the liver and uterus relative to bioidentical human estrogens like estradiol and estrone. Because of their disproportionate potency in the liver,<unk>  and CEEs have relatively increased effects on liver protein synthesis compared to estradiol. A dosage of 0.25 mg/day<unk>  sulfate is<unk> uivalent to 0.625 mg/day CEEs in terms of relief from hot flashes. At a dosage of 0.625 mg/day<unk>  sulfate, the increases in circulating levels of sex hormone-binding globulin (SHBG), corticosteroid-binding globulin, and angiotensinogen were 1.5 to 8 times those observed with estrone sulfate.<unk>  has about 42% of the relative potency of CEEs in the vagina and 80% of the relative potency of CEEs in the uterus, while its more active form, 17β-dihydroequilin, has about 83% of the relative potency of CEEs in the vagina and 200% of the relative potency of CEEs in the uterus. Pharmacokinetics<unk>  has about 8% of the relative binding affinity of testosterone for SHBG, relative to 12% in the case of estrone. In terms of plasma protein binding, it is bound 26% to SHBG and 13% to albumin. The metabolic clearance rates of<unk>  and<unk>  sulfate are 2,640 L/day/m2 and 175 L/day/m2, respectively. In accordance, the biological half-life of<unk>  sulfate is substantially longer than that of<unk> .<unk>  is converted into 17β-dihydroequilin in the liver and in other tissues.<unk>  and 17β-dihydroequilin can also be transformed into<unk> in and 17β-dihydroequilenin.<unk>  is excreted in the form of glucuronide conjugates.
Equilin
Zonulin
Hippulin
Apamin
Collectin
Progerin
Fasciculin
Retapamulin