Study of the effect of inhibition of c-Kit and Cx43 on bladder contractile function and its mechanism of action / 安徽医科大学学报

ABSTRACT

Objective @#To investigation of the interaction between interstitial cells of Cajal (ICCs) and connexin 43 ( Cx43) in bladder contraction and its significance．@*Methods @#Eighty male guinea pigs were randomly divided into blank control group，Glivec group，Gap27 group and Glivec + Gap27 group．Four groups of guinea pigs were per- fused with saline，Glivec，Gap 27，and Glivec + Gap 27 every morning for 2 months．Success of urodynamic testing model after 2 months．Bladder tissue was collected for an in vitro muscle strip test to detect muscle contraction in each group．Correlation between c-Kit and Cx43 was detected by immunofluorescence．The interaction between c- Kit and Cx43 in the bladder was further validated by qRT-PCR and Western blot．Ultrastructural changes in the muscle layer of the bladder were observed by electron microscopy. @*Results @#Urodynamics revealed increased blad- der compliance in the experimental group compared to the blank control group (P＜0. 05) ; bladder compliance increased in the Glivec + Gap27 group compared to the Glivec and Gap27 groups (P＜0. 01) ．In vitro muscle strip experiments revealed that the frequency and tone of bladder muscle strip contractions were lower in the experimental group compared to the blank control group (P＜0. 05) ，and that muscle strip contractions were weaker in the ex- perimental group after administration of acetylcholine (ACH) compared to the control group(P＜0. 05) ．Immuno- fluorescence showed that c-Kit was co-expressed with Cx43 on ICCs cells．qRT-PCR and Western blot suggested that the protein expression level and gene expression level of Cx43 in bladder tissues were lower after inhibition of c-Kit than in the blank control (P＜0. 05) ; after inhibition of Cx43，the protein expression level and gene expres- sion level of c-Kit in bladder tissues the levels of c-Kit protein expression and gene expression in bladder tissues were lower than those in the blank control group (P＜0. 05) ．Electron microscopy revealed that the mitochondrial structure of bladder smooth muscle was disrupted after simultaneous inhibition of c-Kit and Cx43．@*Conclusion@#Cx43 is expressed on bladder ICCs and the two may be jointly involved in regulating bladder contractile function ; the joint reduction of Cx43 and c-Kit may have disrupted the mitochondria of bladder smooth muscle，affecting its function and consequently bladder contractile function.