Expression Of Gap Junction Connexin43 In Detrusor Instability In The Bladder Wall

Purpose: To study the expression of gap junction connexin43 and vimentin in thebladder wall. To elucidate the relationship between connexin43 and interstitial cellsas well as their chance and pathogenesis of detrusor instability(DI).Materials and Methods: Sixteen female SD(Sprague-Dawley,200±10g)rats had asilk ligature placed around the bladder neck to induce BOO; Controls includedeight sham-operated animals. After six weeks, urodynamics without anesthesiawas performed with the rats of the operated and the sham-operated groups.Immunohistochemistry methods were used to detect the expression of Cx43 andvimentin in bladder wall.Results: BOO was successfully established in fifteen among sixteen SD rats. Invivo cystometric studies found eleven SD rats created DI . The rat of DI was 73%.The sham-operated SD rats didn't product DI . HE staining showed that there weretwo changes in the obstructed bladder mucosa : (1) The bladder mucosa becamethick and the arrangement of urothelial cells was disordered .The bladder urothelialcells were intact without necrotic cells; (2) The bladder mucosa became thin anddiscontinuous, and even deficient . The surface of the bladder mucosa wasn'tsmooth and there were a lot of necrotic cells divorced from mucosa . Two changesmay emerge the different or same bladder of the DI rats . Gap junction Cx43 andvimentin were expressed in DI and sham-operated groups . They were localized tothe bladder lamina propria and between the detrusor bundles . The detrusor cellshaven't the expression of Cx43 . Cx43 and vimentin appeared to be less marked indetrusor bundles . Positive rates of Cx43 and vimentin in DI group weresignificantly higher than in sham-operated group.Conclusions: The model of BOO was reliable for this study. Urodynamics withoutanesthesia was one of accurate methods . Cx43 was expressed by interstitial cells.The detrusor smooth muscle cells didn't express Cx43 . There is an increase inCx43 and vimentin levels in DI , suggesting that the increase of communicationbetween interstitial cells is associated with DI.