Aim: Sildenafil potentiates the nitric oxide (NO) signaling pathway. Since neuronal NOS is very important in the penis, we assessed whether NOS1 polymorphisms are associated with altered responsiveness to sildenafil in erectile dysfunction (ED).
Materials & methods: Patients (n = 137) were divided as clinical ED or postoperative ED. They were subdivided as good responders or poor responders to sildenafil, and genotypes for rs41279104 and rs2682826 NOS1 polymorphisms were determined.
Results: We found that the rs41279104 CT genotype was associated with good responders in postoperative ED patients, while rs2682826 CT genotype was associated with good responders in postoperative ED, and the TT genotype associated with good responders in both groups. Finally, the CT haplotype was associated with good responders in postoperative ED.
Conclusion: NOS1 polymorphisms are associated with responsiveness to sildenafil in ED. Original submitted 20 November 2013; Revision submitted 31 January 2014.
Keywords: NOS1; erectile dysfunction; nitric oxide; polymorphisms; prostatectomy; sildenafil.