代谢
Estretol在口服给药后会被大量代谢。雌激素的第二阶段代谢会形成葡萄糖醛酸和硫酸盐结合物,这些结合物在体外几乎不具有雌激素活性。体外代谢研究表明,UGT2B7催化E4-16-葡萄糖醛酸的形成。Estetrol与[drospirenone]结合在一个产品中。[肝细胞色素酶CYP3A4将drospirenone代谢为两种主要代谢物:通过开环形成drospirenone的酸形式和通过还原然后硫酸化形成的4,5二氢drospirenone。这两种代谢物在药理上是无效的。
Estretol is heavily metabolized after oral administration. Phase 2 metabolism of estrogen forms glucuronide and sulfate conjugates with negligible in-vitro estrogenic activity. In vitro metabolism studies demonstrate that UGT2B7 catalyzes the formation of E4-16-glucuronide. Estetrol is combined with [drospirenone] in a product. The hepatic cytochrome enzyme CYP3A4 metabolizes drospirenone to two primary metabolites: the acid form of drospirenone through the opening of the lactone ring and the 4,5 dihydrodrospirenone formed by reduction, followed by sulfation. Both metabolites are pharmacologically inactive.
来源:DrugBank