Effect of co-administration of BRL-37344 and tadalafil on reduction of overactive bladder symptoms after induction of detrusor overactivity in mice

Purpose: To evaluate the impact of the combination of BRL 37344 and tadalafil (TDF) on the reduction of overactive bladder (OB) symptoms. Methods: Thirty mice were randomized into 5 groups (G) of 6 animals each. L-NAME was used to induce DO. G1: Control; G2: L-NAME; G3: L-NAME + TDF; G4: L-NAME + BRL 37344; G5: L-NAME + TDF + BRL 37344. After 30 days of treatment, the animals were submitted to cystometry to evaluate non-voiding contractions (NVC), threshold pressure (TP), baseline pressure (BP), frequency of micturition (FM) and threshold volume (TV). Differences between the groups were analyzed with ANOVA followed by the Tukey test. Results: NVC increased in G2 (4.33±2.58) in relation to G1 (1.50±0.55). NVC decreased in G3 (2.00±1.10), G4 (1.50±1.52) and G5 (2.00±1.26) compared to G2 (p<0.05). FM decreased in G3 (0.97±0.71), G4 (0.92±0.38) and G5 (1.05±0.44) compared to G2 (p<0.05). However, the combination of TDF and BRL37344 was not more effective at increasing NVC and improving FM than either drug alone. The five groups did not differ significantly with regard to TV. Conclusion: The combination of BRL 37344 and TDF produced no measurable additive effect on reduction of OB symptoms.