Mesterolone is a synthetic anabolic-androgenic steroid (AAS) and derivative of dihydrotestosterone (DHT). It is inactivated by 3α-hydroxysteroid dehydrogenase in skeleta muscules so it is considered a weak androgen. Mesterolone is an androgen receptor agonist which was developed for hormone replacement therapy in males suffering from androgen deficiency and related disorders.
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