Harris A, Kagemann L, Ehrlich R, Ehrlich Y, López C R, Purvin V A
Department of Ophthalmology, Indiana University School of Medicine, 702 Rotary Circle, Indianapolis, IN 46202, USA.
Br J Ophthalmol. 2008 Apr;92(4):469-73. doi: 10.1136/bjo.2007.131789.
Sildenafil is a potent phosphodiesterase (PDE) 5 inhibitor that is used for patients with erectile dysfunction. Sildenafil induces vasodilation in selected smooth muscle via increased levels of guanosine 3', 5' cyclic monophosphate and increase in nitric oxide. The vasodilatory effects of the PDE 5 inhibitors led us to review its effect on the ocular vasculature. Sildenafil appears to increase blood flow velocity significantly in the retrobulbar and choroidal circulation. Most studies suggest an increase in choroidal blood flow, with a lesser effect on the retinal vasculature.
西地那非是一种强效磷酸二酯酶（PDE）5抑制剂，用于治疗勃起功能障碍患者。西地那非通过增加3',5'-环磷酸鸟苷水平和一氧化氮水平，在特定平滑肌中诱导血管舒张。PDE 5抑制剂的血管舒张作用促使我们研究其对眼部血管系统的影响。西地那非似乎能显著提高球后和脉络膜循环的血流速度。大多数研究表明脉络膜血流增加，对视网膜血管系统的影响较小。
