Phosphodiesterase 5 inhibitors attenuate renal tubular apoptosis after partial unilateral ureteral obstruction: An experimental study

The aim of the present study was to evaluate the effects of phosphodiesterase 5 inhibitors on renal tubular apoptosis and also on expressions of endothelial and inducible nitric oxide synthases (eNOS and iNOS) in the ipsilateral kidney after partial unilateral ureteral obstruction (PUUO) in a rat model. Forty Wistar albino rats were divided into five groups. In Groups 1–4, left experimental PUUO was created. Sildenafil, vardenafil, and tadalafil were administrated to the rats of Groups 2–4, respectively. The pills were orally given to the rats for 30 days. Group 5 was defined as sham. After 30 days, all rats were sacrificed, and nephrectomy was performed. The renal specimens were examined histopathologically. Left hydroureteronephrosis was observed in Groups 1–4. Mean apoptotic cell count and eNOS and iNOS levels were significantly increased in Group 1 when compared with the other groups. The rats in Groups 2–4 showed significantly decreased apoptotic cell count and eNOS and iNOS values in the renal tubular tissue in accordance with Group 1 (p < 0.05). There were significant differences in apoptotic cell counts between sildenafil group and the other two study groups. The sildenafil group demonstrated lesser apoptotic cell count than the vardenafil (p = 0.021) and tadalafil (p = 0.009) groups. PUUO increases the renal tubular apoptosis and elevates NOS concentrations in renal tubular tissue after PUUO. Phosphodiesterase 5 inhibitors have a protective effect against the tubular apoptosis.