蛋白激酶C在糖尿病周围神经病变中的表达及中药干预的实验研究

An experimental study of the expression of protein kinase C in diabetic peripheral neuropathy and chinese medicinal herbs interposition

目的 蛋白激酶C(PKC)与糖尿病(DM)及其并发症的关系已成为研究的焦点,本实验检测了DM大鼠坐骨神经及腓肠肌PKC -beta表达及活性变化,探讨PKC在糖尿病周围神经病变(DPN)发病中的作用,并观察中药对其影响。方法 利用(γ -32P)ATP底物磷酸化方法检测实验对照组、中药组DM大鼠及正常组大鼠坐骨神经及腓肠肌的胞浆、胞膜PKC-beta活性,并行免疫印迹分析PKC- beta在神经肌肉组织中的表达。结果 实验 2个月,两组DM大鼠坐骨神经及腓肠肌的胞浆、胞膜PKC beta活性与正常组大鼠比较均增高,实验对照组增高明显,中药组稍高于正常组。PKC- beta表达与活性测定结果相一致。结果提示实验对照组坐骨神经及腓肠肌部位PKC- beta表达明显增加,活性明显增高,而中药组接近正常组。结论 实验性 2个月DM大鼠周围神经病变中的PKC- beta表达及活性明显增加,本中药复方对其有一定抑制作用。

Objective To investigate the role of protein kinase C (PKC) in the pathogenesis of diabetic peripheral neuropathy(DPN) by measuring PKC activities and expressions in the sciatic nerves and gastrocnemius muscles of diabetic rats induced by streptozotocin,and the effect of Chinese medicinal herbs (CMH) on its was observed too. Methods PKC activity of membranous and cytosolic fractions in the sciatic nerves and gastrocnemius muscles of each groups: untreated, CMH-treated diabeticrats, untreated normalrats was measured by its ability to transfer 32P from (gamma- 32P)ATP into the PKC-specific substrate. PKC expression was analyzed by western blot too.Results On the 2-months the results showed: PKC activities in either cytosolic or Membranous fractions of sciatic nerves and gastricnemius muscles were increased in the Untreated and CMH-treated diabetic rats compared with that in normal rats, and increased PKC activities in untreated diabetic rats were conspicuous. PKC activity in CMH-treated diabetic rats is similar to that in normal rats. The result of PKC expression by western blot are consistent with that of measured PKC activity. The result indicated that PKC activities and expressions in sciatic nerves and gastricnemius muscles of untreated diabetic rats increased conspicuously, alteration of CMH-treated diabetic rats not evident.Conclusion PKC expression and activity in DPN of STZ-induced diabetic rats on the 2-months were increased conspicuously, the CMH could possess certain inhibitory effects on the alteration.