枸橼酸西地那非（50毫克）产品是Sildenafil citrate is a potent, orally active phosphodiesterase 5 (PDE5) inhibitor (IC₅₀ = 4 nM). Inhibition of PDE5 enhances the relaxation of smooth muscle in a range of vascular tissues by prolonging the nitric oxide/cGMP-mediated activation of cGMP-dependent protein kinase (PKG). Sildenafil also acts as a vasodilator and this property has been used to control vascular tone in pulmonary arterial hypertension and high-altitude pulmonary edema associated with altitude sickness.
