Silodosin and tadalafil have synergistic inhibitory effects on nerve-mediated contractions of human and rat isolated prostates
Abstract
Lower urinary tract symptoms (LUTS) in men with benign prostatic hyperplasia (BPH) are associated with erectile dysfunction. Alpha-1-adrenoceptor antagonists are effective drugs for treating symptomatic BPH. Clinical data show improvements in LUTS by phosphodiesterase 5 inhibitors. This study aimed to evaluate effects of silodosin, a highly selective α1A-adrenoceptor antagonist, alone or in combination with the phosphodiesterase 5 inhibitor tadalafil on contractions of isolated human and rat prostates. In organbath studies, effects of increasing concentrations of silodosin (1 nM-1 µM) and tadalafil (100 nM-100 µM) on contractions by electrical field stimulation or phenylephrine of human and rat prostate strip preparations were investigated. The combination silodosin and tadalafil reduced electrically-induced contractions of human prostate preparations better than single drugs alone. At any frequencies (1-32 Hz), inhibitory effects of combined therapy (P-values vs single drug) in human tissue were 26-42% (1 nM silodosin+100 nM tadalafil; P<0.05), 40-58% (10 nM silodosin+1 µM tadalafil; P<0.001-0.05), 56-67% (100 nM silodosin+10 µM tadalafil; P<0.01-0.05), and 33-55% (1 µM silodosin+100 µM tadalafil P<0.01-0.05). Similar findings were obtained in rat prostate preparations. In human and rat prostate tissue, the drug combination exerted similar inhibitory effect on phenylephrine contractions as silodosin alone. Silodosin plus tadalafil had greater potency than each drug alone to…
Read the paper
Related studies
- Erectile dysfunction
- Testosterone protects from metabolic syndrome-associated prostate inflammation: an experimental study in rabbit
- Alpha1-adrenoceptor subtypes and lower urinary tract symptoms
- Cyclic nucleotide phosphodiesterases: important signaling modulators and therapeutic targets
- Chronic bladder ischemia and oxidative stress: New pharmacotherapeutic targets for lower urinary tract symptoms
- The role of prostate inflammation and fibrosis in lower urinary tract symptoms
Go deeper in Evidence Hub
Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.