A synthetic non-aromatizable androgen and anabolic steroid. It binds strongly to the androgen receptor and has therefore also been used as an affinity label for this receptor in the prostate and in prostatic tumors.
Biochem/physiol Actions Androgen receptors (ARs) are nuclear hormone receptors/transcription factors. R1881, also known as methyltrienolone, is a synthetic androgen. It is the gold standard AR agonist.