131MATURATION AND RELAXATION TO PHOSPHODIESTERASE INHIBITORS IN RAT URINARY BLADDERPrevious studies suggest that age-related changes play major roles in the control of urinary bladder tone, especially in women. Here, we investigated the responsiveness of phosphodiesterase inhibitors (PDEis) in urinary bladder strips from young (2-3 months) and adult (14-15 months) female Wistar rats. Concentration-response curves of PDE5i tadalafil (10 -9 -10 -3 M)-induced relaxation were generated against carbachol (10 -6 M)-induced tone in both age groups, in the absence or presence of the PDE3i cilostazol (10 -6 M). Tadalafil concentration dependently relaxed bladder strips and maturation significantly increased the sensitivity. In addition, cilostazol (10 -6 M) significantly potentiated relaxations to tadalafil in both age groups.The results indicate that in urinary bladder, there is an increase in PDE-mediated responses in maturationesraatalik@hotmail.comResearch712017Cilostazol,Maturation,Tadalafil,Urinary bladderNurullahoglu-Atalik Kismet Esra,Kutlu Selim,Solak Hatice,Ozen Koca RaviyeDepartment of Pharmacology, University of Necmettin Erbakan, Konya, 42080, Türkiye,Physiology, Meram Faculty of Medicine, University of Necmettin Erbakan, Konya, 42080, Türkiye,Physiology, Meram Faculty of Medicine, University of Necmettin Erbakan, Konya, 42080, Türkiye,Physiology, Meram Faculty of Medicine, University of Necmettin Erbakan, Konya, 42080, Türkiye