Purpose

The overactive bladder (OAB) syndrome is characterized by urgency usually with frequency and nocturia. Tamsulosin, α1-adrenergic receptor antagonist, is widely used to reduce symptoms of urinary obstruction and prostatic hyperplasia. Tamsulosin can across the blood-brain barrier. We investigated the effects of tamsulosin on the symptoms of OAB in relation to neuronal activity using rats.

Methods

Adult female Sprague-Dawley rats, weighing 250±10 g (9 weeks old), were used in this study. The animals were divided into five groups (n=8 in each group): control group, OAB-induced group, OAB-induced and 0.01 mg/kg tamsulosin-treated group, OAB-induced and 0.1 mg/kg tamsulosin-treated group, and OAB-induced and 1 mg/kg tamsulosin-treated group. OAB was induced by intraperitoneal injection of cyclophosphamide (75 mg/kg) every third day for 10 days. The rats in the tamsulosin-treated groups orally received tamsulosin once a day for 14 consecutive days at the respective dose of the groups, starting 1 day after the induction of OAB. Cystometry for bladder pressure determination, immunohistochemistry for c-Fos, nicotinamide adenine dinucleotide phosphate-diaphorase histochemistry for nitric oxide synthase (NOS) in the neuronal voiding centers and western blot for inducible NOS in the bladder were conducted.

Results

Cyclophosphamide injection enhanced contraction pressure and time, representing the induction of OAB. Contraction pressure and time were significantly suppressed by tamsulosin treatment. c-Fos and NOS expressions in the neuronal voiding centers were enhanced by induction of OAB. OAB-induced c-Fos and NOS expressions were suppressed by tamsulosin treatment.

Conclusions

Tamsulosin exerts inhibitory effect on neuronal activation in the neuronal voiding centers of OAB. The present results suggest the possibility that tamsulosin is effective therapeutic modality for ameliorating the symptoms of OAB.

Purpose

Although the quality of life (QoL) of prostate cancer (PCa) patients is a major issue, there is no unified and useful methodology for assessing QoL. The Expanded Prostate Cancer Index Composite (EPIC) is a globally used tool to measure QoL after PCa treatment that comprises urinary, bowel, sexual, and hormonal domains. Acknowledging the need for such a tool applicable to Korean PCa patients, we translated EPIC into Korean and validated the new version.

Materials and Methods

The Korean version of EPIC was devised by translation, back-translation, and reconciliation. Subsequently, we randomly selected 153 patients with localized PCa treated with radical perineal prostatectomy (67, 43.8%), radical retropubic prostatectomy (19, 12.4%), laparoscopic radical prostatectomy (12, 7.8%), robot-assisted laparoscopic radical prostatectomy (36, 23.5%), and high-intensity focused ultrasound ablation of the prostate (19, 12.4%) and asked them to complete EPIC. Reliability was assessed by test-retest correlation and Cronbach's alpha. Validity was assessed by factor analysis, interscale correlation, and correlation with Functional Assessment of Cancer Therapy-Prostate (FACT-P).

Results

Test-retest correlation and Cronbach's alpha were high in each of the domains (0.92, 0.91, 0.76, 0.84 and 0.86, 0.84, 0.92, 0.83, p<0.0001). Interscale correlation among the domains was low (r<0.37), which indicated that EPIC is composed of proper domains. Interscale correlation between the function and bother subscales was high (0.94, 0.81, 0.84 and 0.80, p<0.0001). EPIC domains had low correlation with FACT-P, permitting complementary use.

Conclusions

The Korean version of EPIC was developed by a proper process, as evident by its high reliability and validity. Therefore, it is a reliable, comprehensive, systematic method that evaluates QoL in Korean patients after PCa treatment. Furthermore, it can be adapted as an objective methodology for research globally.