Debutyldronedarone

Debutyldronedarone is an inhibitor of cytochrome P450 enzymes (Cytochrome P450) and thyroid hormone receptors (Thyroid Hormone Receptor), and is a pharmacologically active metabolite of Dronedarone (HY-A0016). Debutyldronedarone reduces the incidence of reperfusion-induced ventricular fibrillation in anesthetized rats, while decreasing their heart rate and blood pressure. Debutyldronedarone can be used in studies related to ventricular fibrillation and atrial fibrillation^[1][2]. In Vitro:Debutyldronedarone (SR35021) inhibits the binding of T3 to human TRα₁ (K_i = 59 μM) and TRβ₁ (K_i = 280 μM) in vitro, with higher potency against the TRα₁ subtype; it also inhibits multiple human CYP isozymes in vitro, with K_i values ranging from 4.37 μM (CYP2D6) to 56.9 μM (CYP2B6)^[1].
Debutyldronedarone binds extensively to human plasma proteins (98.5%) and purified serum albumin (94.5-95.3%) in a non-saturable manner, whereas its binding to α₁-acid glycoprotein is saturable and concentration-dependent^[1].
Debutyldronedarone is metabolized by human CYP3A and CYP2D6 in vitro^[1].
Debutyldronedarone (DBDron) (10-100 μM) potently and competitively inhibits the binding of [¹²⁵I]T₃ to chicken TRα₁ with an IC₅₀ of 59 μM; meanwhile, it only exerts weak inhibitory effects on the binding of [¹²⁵I]T₃ to human TRβ₁, with an IC₅₀ of 280 μM, demonstrating TRα₁-selective antagonistic activity^[2]. In Vivo:Debutyldronedarone (SR35021) (9.3 mg/kg; intravenous administration; single dose) reduces the incidence of reperfusion-induced ventricular fibrillation in anesthetized rats to a level similar to that of dronedarone administered intravenously at 2.8 mg/kg, while also decreasing heart rate and blood pressure^[1].
Debutyldronedarone (DBDron) (formed in vivo from Dronedarone (HY-A0016); administration conditions: 50-100 mg/kg, p.o., once daily for 14 consecutive days) acts as a thyroid hormone receptor α₁-selective inhibitor. It prolongs the QTc interval to approximately 0.028 msec via TRα₁ mediation, reduces plasma T₃ levels, and does not affect TRβ₁-mediated hepatic lipid metabolism endpoints^[2].