PURPOSE To determine the rates of sildenafil (Viagra) use among different populations, primarily among men who have sex with men, and to measure the association of sildenafil use with increased sexual risk behavior and sexually transmitted diseases (STDs), including human immunodeficiency virus (HIV) infection. METHODS The National Center for Biotechnology Information PubMed was searched usin...

Background—Safe, effective therapy is needed for pediatric pulmonary arterial hypertension. Methods and Results—Children (n 235; weight 8 kg) were randomized to low-, medium-, or high-dose sildenafil or placebo orally 3 times daily for 16 weeks in the Sildenafil in Treatment-Naive Children, Aged 1–17 Years, With Pulmonary Arterial Hypertension (STARTS-1) study. The primary comparison was percen...

BACKGROUND/AIMS Sildenafil, the first selective phosphodiesterase-5 (PDE5) inhibitor to be widely used for treating erectile dysfunction, has been investigated with regard to its cardioand renoprotective effects in animal models. This study further investigated the renoprotective effects of sildenafil and their molecular mechanisms in deoxycorticosterone acetate (DOCA)-salt hypertensive (DSH) r...

PURPOSE To determine, in men with erectile dysfunction (ED), the extent of improvement in erection hardness and in the rate of successful sexual intercourse (SSI) during the final intercourse attempt using sildenafil 50 mg compared with the subsequent initial attempt after a dose increase to 100 mg. PATIENTS AND METHODS This post hoc analysis used data from two randomized, double-blind, place...

PURPOSE The effects of pioglitazone on sildenafil responsiveness in men with erectile dysfunction(ED) and a history of poor response to sildenafil were assessed. METHODS In a double-blinded study,38 men aged 47 +/- 1.5 years with moderate-to severe ED and poor response to sildenafil were randomly assigned to take a premedication of pioglitazone 30 mg (n=19) or placebo (n=19) once daily for 9 ...

Sildenafil increases the cyclic guanosine monophosphate (cGMP) by inhibition of a phosphodiesterase 5, thereby leading to an antinociceptive effect. The increased cGMP may exert the effect on an L-type calcium channel through the activation of protein kinase G (PKG). The purpose of this study was to examine the possible involvement of a PKG-Ltype calcium channel on the effect of sildenafil at t...

We examined the interaction between OSU-03012 (also called AR-12) with phosphodiesterase 5 (PDE5) inhibitors to determine the role of the chaperone glucose-regulated protein (GRP78)/BiP/HSPA5 in the cellular response. Sildenafil (Viagra) interacted in a greater than additive fashion with OSU-03012 to kill stem-like GBM cells. Treatment of cells with OSU-03012/sildenafil: abolished the expressio...

Background: Sildenafil (Viagra) has been introduced to treat erectile dysfunction by acting as phosphodiesterase 5 inhibitor and hence accumulation of guanosine cyclic monophosphate (cGMP). On the other hands, the nitric oxide/cGMP signaling pathway has crucial role in synaptic plasticity processes like long-term potentiation (LTP) in the central nervous system considered as a model of learning...

BACKGROUND Severe burn induces systemic inflammation and reactive oxygen species leading to lipid peroxidation which may play role in remote organs injury. Sildenafil is a selective and potent inhibitor of cyclic guanosine monophosphate specific phosphodiesterase-5. Sildenafil reduces oxidative stress and inflammation in distant organs. The aim of the present study was to evaluate the effects o...

Phosphodiesterase (PDE)-5 degrades guanosine 3',5'cyclic monophosphate (cGMP) and its inhibitor sildenafil citrate (Viagra) treats erectile dysfunction by smooth muscle relaxation through elevated cGMP. Sildenafil was examined in two guinea pig models of airways disease: guinea pigs exposed to LPS or sensitized guinea pigs with atopy exposed to ovalbumen. Ovalbumen exposure caused early- and la...