N-Desmethyl Sildenafil

N-Desmethyl Sildenafil (Desmethylsildenafil) is a major metabolite of Sildenafil. Sildenafil is a potent phosphodiesterase type 5 (PDE5) inhibitor[1][2].

Research Areas >> Cardiovascular Disease

Signaling Pathways >> Metabolic Enzyme/Protease >> Phosphodiesterase (PDE)

N-Desmethyl Sildenafil increases the amplitude of electroretinogram (ERG) recorded from the dark-adapted isolated rat retina, most probably through the enhancement of the photoreceptor cell response[1]. The formation of N-Desmethyl Sildenafil is examined using CYP3A supersomes co-expressing human P450 oxidoreductase and cytochrome b5. N-Desmethyl Sildenafil is catalyzed by CYP3A4, CYP3A5, and to a lesser extent by CYP3A7[2].

[1]. Péter Barabás, et al. Sildenafil, N-desmethyl-sildenafil and Zaprinast enhance photoreceptor response in the isolated rat retina. Neurochem Int. 2003 Nov;43(6):591-5.

[2]. Rikako Takahiro, et al. Contribution of CYP3A isoforms to dealkylation of PDE5 inhibitors: a comparison between sildenafil N-demethylation and tadalafil demethylenation. Biol Pharm Bull. 2015;38(1):58-65.