OBJECTIVE Mutations in the bone morphogenetic protein type II receptor (BMPR-II) are responsible for the majority of cases of heritable pulmonary arterial hypertension (PAH), and BMPR-II deficiency contributes to idiopathic and experimental forms of PAH. Sildenafil, a potent type-5 nucleotide-dependent phosphodiesterase inhibitor, is an established treatment for PAH, but whether sildenafil affe...

INTRODUCTION Insulin resistance features both endothelial dysfunction and increased oxidative stress. Both disorders are targeted by a chronic treatment with sildenafil. However, the mechanism of action by which chronic sildenafil exerts its effects on reactive oxygen species sources is still largely unknown. AIM We therefore investigated how chronic sildenafil administration could impact vas...

Sildenafil induces vasodilation and is used for treating erectile dysfunction. Although its influence on resting heart function appears to be minimal, recent studies suggest that sildenafil can increase sympathetic activity. We therefore tested whether sildenafil injected into the central nervous system alters the autonomic control of the cardiovascular system in conscious rats. The effect of s...

Acute phosphodiesterase 5A inhibition by sildenafil or EMD360527/5 promoted profound inhibition of the cardiac Na(+)/H(+) exchanger (NHE-1), detected by the almost null intracellular pH recovery from an acute acid load (ammonium prepulse) in isolated papillary muscles from Wistar rats. Inhibition of phosphoglycerate kinase-1 (KT5823) restored normal NHE-1 activity, suggesting a causal link betw...

The phosphodiesterase type-5 inhibitor sildenafil has powerful cardioprotective effects against ischemia-reperfusion injury. PKG-mediated signaling has been implicated in this protection, although the mechanism and the downstream targets of this kinase remain to be fully elucidated. In this study we assessed the role of phospholemman (PLM) phosphorylation, which activates the Na(+)/K(+)-ATPase,...

INTRODUCTION Viagra (sildenafil citrate) has a rapid onset of action for the treatment of erectile dysfunction (ED). However, its duration of action has not been thoroughly investigated. Practical knowledge of the time window available for sexual intercourse would be valuable for couples planning sexual activity. AIM We investigated the duration of action of sildenafil in men with ED. METHO...

Background: Sildenafil causes vasodilatation by relaxing the smooth muscles of blood vessels. This enhances endometrial development, the health of which is indispensable for implantation and embryonic and fetal development. Aim: To assess the role of Sildenafil when used in ovulation induction cycles with Clomiphene Citrate (CC) with reference to Endometrial Thickness (ET), follicular developme...

BACKGROUND Sildenafil, a phosphodiestase type 5 inhibitor, was approved in 2005 for the treatment of pulmonary arterial hypertension (PAH) in adults and is commonly used off-label for pediatric patients. Little is known, however, about sildenafil's side effects in this population. METHODS Single institution, longitudinal survey-based study performed in an outpatient pediatric cardiology clini...

BACKGROUND Erectile dysfunction (ED) is common in men with renal failure, but is not always alleviated following kidney transplant. The objective of the present study was to assess the feasibility in renal transplant patients of sildenafil citrate treatment, an agent with proven efficacy in the management of ED. METHODS This was a phase IV, open, multicentre, 3 month, dose-escalation study. A...

In this study, the effects of sildenafil administration on penile erection and semen volume and characteristics in Kangal dogs were studied. A total of 5 Kangal dogs, aging 3-6 years, and with a known fertility were used. In each application, sildenafil was administered orally at a dosage of 50 mg, 60 minutes prior to semen collection. Semen was collected 12 times at 3-day intervals by digital ...