Therapeutic effects of connexin inhibitors on detrusor overactivity induced by bladder outlet obstruction in rats

Objectives: To investigate the alterations in Connexin 43 (Cx43) and connexin 26 (Cx26) levels in the bladder outlet obstruction (BOO)-induced detrusor overactivity and examine the effect of connexin inhibitors on this condition. Methods: Fifty Sprague-Dawley rats were divided into 4 groups: sham-operated control group (n = 10), BOO group (n = 10), and 2 groups that were administered connexin inhibitors. The first of these 2 groups was administered 18β-glycyrrhetinic acid (BOO-18β-GA group, n = 15) and the second group was given oleamide (BOO-oleamide group, n = 15). Cystometrogram was performed in all groups after 2 weeks of obstruction. The expression levels of Cx26 and Cx43 were analyzed using immunohistochemical staining and Western blot. Results: The intercontraction interval was markedly shorter in the BOO group compared with the control group (P <.05). Intercontraction intervals in the BOO-18β-GA and BOO-oleamide groups at 2 weeks were significantly longer than that observed for the BOO group (P <.05). The expression of Cx43 and Cx26 were increased in the BOO group. After administration of connexin inhibitors, downregulation of Cx43 and Cx26 was noted. Conclusions: These results suggest that upregulation of Cx43 and Cx26 induce detrusor overactivity after BOO, and connexin inhibitors may have some role in relieving BOO-induced detrusor overactivity in rats.