糖尿病膀胱病大鼠膀胱Cajal间质细胞丙酮酸激酶表达及活性改变

Expression and activity of pyruvate kinase in bladder interstitial cells of cajal in rats with diabetic cystopathy

目的检测糖尿病膀胱病(DCP)大鼠膀胱Cajal间质细胞(ICCs)丙酮酸激酶(PKM)的表达和活性,探讨其在DCP发病机制中的作用。方法40只雌性SD大鼠,9只为正常对照组;31只以腹腔注射链脲佐菌素法建立糖尿病大鼠模型,18只建立成功;9只糖尿病大鼠继续饲养12周,建立DCP大鼠。对照组、糖尿病组、DCP组大鼠分别取膀胱肌层ICCs细胞培养,Western blot及定量PCR法检测PKM蛋白和mRNA,并进行PKM活性测定。结果DCP组大鼠膀胱ICCs细胞内PKM蛋白、mRNA、活性值分别为(0.537±0.015)、(0.624±0.026)、(0.098±0.010) U/g蛋白;而糖尿病和对照组大鼠分别为(0.722±0.026)、(0.739±0.045)、(0.178±0.017) U/g蛋白与(0.923±0.031)、(1.000±0.022)、(0.277±0.030) U/g蛋白;DCP大鼠ICCs细胞内PKM表达及活性值较糖尿病组及对照组明显下降(P<0.01)。结论膀胱ICCs细胞内PKM活性下降是DCP发生发展的重要机制之一。

Objective To investigate the expression and activity of pyruvate kinase in interstitial cells of Cajal (ICCs) in the bladder of rats with diabetic cystopathy (DCP). Methods Forty 8-week-old female rats were divided into two groups randomly, 31 as the experiment group and the rest 9 as the control group. The experiment group was intraperitoneally injected with streptozotocin (STZ) to establish diabetic models and 18 rats were succeeded to be induced. Nine diabetic rats were further raised for 12 weeks getting DCP rats. ICCs from bladder muscle were cultured. The expression of pyruvate kinase protein and mRNA was detected by Western blotting and real-time quantitative polymerase chain reaction (Real-time PCR) respectively, and pyruvate kinase activity was measured. Results The expression levels of pyruvate kinase protein and mRNA and activity in DCP rats were reduced significantly as compared with those of the diabetic rats and control rats [(0.537±0.015),(0.624±0.026),(0.098±0.010) U/g·prot respectively, vs.(0.722±0.026),(0.739±0.045),(0.178±0.017) U/g·prot, vs.(0.923±0.031),(1.000±0.022),(0.277±0.030) U/g·prot;P<0.01]. Conclusion The reduction of pyruvate kinase activity in ICCs may play an important role in the development of DCP.