Naftopidil Improves Symptoms in a Rat Model of Tranilast-Induced Interstitial Cystitis

ObjectiveThe effect of naftopidil on symptoms of tranilast-induced interstitial cystitis (IC) was examined in rats. MethodsThirty-two female rats were divided into four groups (control, naftopidil, tranilast, and combination groups). Rats in the control group were fed a standard diet, while rats in the naftopidil, tranilast, and combination groups were fed diets containing naftopidil, tranilast, or naftopidil+tranilast, respectively. After 4weeks of treatment, locomotor activity was measured and continuous cystometry was performed. ResultsDuring the light period, locomotor activity was lower in the tranilast group than in the control, naftopidil, and combination groups. During the dark period, locomotor activity was higher in the naftopidil group than in the other three groups. The combination group showed higher locomotor activity than the tranilast group, but significantly lower activity than the naftopidil group. Continuous cystometry revealed that the interval between bladder contractions was shorter in the tranilast group than in the other three groups. The combination group also had a shorter interval between contractions than the control group. ConclusionNaftopidil improved the symptoms of tranilast-induced IC, such as reduced locomotor activity due to pelvic pain and a shortened interval between bladder contractions. Therefore, naftopidil may be a potential treatment for IC.