瘦素对糖尿病心肌病大鼠血清IL-6和Ang-Ⅱ水平的影响

Effect of leptin on serum levels of IL-6 and Ang-Ⅱin diabetic cardiomyopathy rats

目的:通过大鼠糖尿病性心肌病(DCM)模型,探讨瘦素对白细胞介素-6(IL-6)、血管紧张素-Ⅱ(Ang-Ⅱ)的影响。方法:采用腹腔注射链脲佐菌素(STZ)造大鼠模型。将DCM大鼠随机分为DCM组、瘦素50μg/kg组、瘦素100μg/kg组,每组10只,3组大鼠造模成功后均继续给予高脂高糖饮食,瘦素50μg/kg组、瘦素100μg/kg组分别给予每日腹腔注射瘦素50μg/kg、100μg/kg,持续5d。另设正常对照组10只给予常规饲料,4组的饲养时间均为12周。12周后检测血清IL-6、Ang-Ⅱ水平,并行心脏彩超测定大鼠的左室舒张末压(LVEDP)、左室舒张末期内径(LVIDd)及左室射血分数(LVEF)。结果:与对照组相比,DCM组大鼠出现心功能减退,IL-6、Ang-Ⅱ水平升高(P<0.01);不同剂量的瘦素干预后,大鼠心功能减退严重,IL-6、Ang-Ⅱ水平也显著升高(P<0.01),且瘦素100μg/kg组变化更为明显。结论:瘦素可能在糖尿病心肌病的发生发展中起着重要作用,其机制可能是通过激活部分炎症因子及肾交感神经系统实现的。

Objective： To investigate the effect of leptin on serum levels of IL-6 and Ang-Ⅱ in diabetic cardiomyopathy rats through DCM of rats. Methods： DCM rats were intraperitoneally injected with streptozocin （STZ） to create rat models. DCM rats were randomized into 3 groups： the DCM group （n=10）, the 50μg/kgleptingroup （n=10）, and thel00μg/kgleptingroup （n=10）. Thediabetic cardiomyopathy rats of the 3 groups were continuously given high energy diet after the models were successfully induced. The latter two groups were subjected to leptin at a dosage of 50 μg/kg and 100μg/kg for 5 days respectively. Another 10 rats in the normal control group were given normal diet. And the feeding time of the four groups lasted 12 weeks. After 12 weeks, serum IL-6 and Ang-Ⅱ were detected, and LVEDP, LVIDd and LVEF were determined by color doppler ultrasound. Results： Heart function failed in the DCM rats, while serum IL-6 and Ang-Ⅱ in DCM groups was significantly higher than that of the control group （P〈0.01）. After the intervention of different dose of leptin, the cardiac function declined more severely, while the serum IL-6 and Ang-Ⅱ was obviusly higher （P〈0. 01）, and especially for rats in the I00 btg/kg leptin group. Conclusion： Leptin may play an important role in the occurrence and development of diabetic cardiomyopathy, and the activation of the renal sympathetic nervous System and the inflammatory factors may be one of the pathologiesis mechanism of the diabetic cardiomyopathy.