缝隙连接蛋白-43在糖尿病膀胱豚鼠模型中的表达及意义

Expression and significance of connexin-43 in guinea pig model of diabetic cystopathy

目的探讨缝隙连接蛋白-43(Cx43)在豚鼠糖尿病膀胱(DCP)中的表达情况及其意义。方法 50只豚鼠随机分为DCP组(n=30)、枸橼酸钠组(n=10)、空白对照组(n=10),DCP组豚鼠单次腹腔注射链脲佐菌素建立糖尿病模型,利用尿动力学检测筛选出糖尿病膀胱豚鼠;枸橼酸钠组豚鼠单次腹腔注射枸橼酸钠溶液;空白对照组豚鼠单次腹腔注射生理盐水;通过免疫组织化学染色法观察Cx43在3组膀胱逼尿肌中的定位及分布,采用Western blot技术检测3组膀胱逼尿肌组织内Cx43蛋白的表达。结果免疫组织化学染色结果显示,DCP组(筛选出DCP豚鼠共10只纳入研究)Cx43特异性染色强度较其他2组明显降低,枸橼酸钠组和空白对照组阳性染色强度对比无明显差异。Western blot检测发现,DCP组膀胱组织Cx43蛋白表达(0.52±0.02)低于空白对照组(0.68±0.02)和枸橼酸钠组(0.70±0.03)(P<0.01),空白对照组与枸橼酸钠组膀胱组织Cx43蛋白表达差异无统计学意义(P>0.05)。结论逼尿肌组织Cx43的表达降低在糖尿病膀胱的形成过程中起重要作用,可能成为研究糖尿病膀胱发病机制的新出发点。

Objective To investigate the expression of connexin43(Cx43) in diabetic cystopathy(DCP) and study its significance.Methods Fifty guinea pigs were randomly divided into DCP group(n=30),sodium citrate group(n=10) and blank control group(n=10).Diabetic model was established by intraperitoneal injection of streptozotocin in DCP group.Diabetic bladder guinea pigs were screened by urodynamics test.The sodium group was intraperitoneally injected with sodium citrate solution,and the blank control group was injected intraperitoneally with normal saline.The location and distribution of Cx43 in the three groups of bladder detrusor were observed by immunohistochemical staining,and expressions of Cx43 proteins were detected by Western blot assay.Results Immunohistochemical staining showed that the intensity of Cx43-specific staining was significantly lower in DCP group than that in the other two groups.There was no significant difference in the positive staining intensity between sodium citrate group and blank control group.Western blot analysis showed that the expression of Cx43 protein was significantly lower in bladder tissue of DCP group(0.52±0.02) than that of blank control group(0.68±0.02) and sodium citrate group(0.70±0.03,P<0.01).There was no significant difference in the expression of Cx43 protein in the bladder tissue between the sodium citrate group and blank control group(P>0.01).Conclusion The decreased expression of Cx43 in detrusor tissue plays an important role in the formation of diabetic bladder and may be a new starting point for studying the pathogenesis of diabetic bladder.