围体外循环期肿瘤坏死因子与胰岛素抵抗

Expression of TNF-mRNA and lnsulin Resistance in Skeletal and Cardiac Muscle during Cardiopulmonary Bypass

目的 探讨体外循环 (Cardiopulmonarybypass,CPB)心血管手术中的胰岛素抵抗发生与肌肉组织TNF -αmRNA表达的关系。方法 10例心脏直视手术患者 ,分别在麻醉前、CPB前、CPB 15min、开放升主动脉后 5min和停CPB 2 0min采血样 ,测定胰岛素、C肽、肿瘤坏死因子、血糖和红细胞压积 ,计算胰岛素敏感性指数 [l/(IxG) ]。分别于劈胸骨和关胸时在胸部正中切口下缘取腹直肌 1g ,于静脉插管和缝合房壁时在右房取小块心房组织 1g。用Trizol试剂提取总RNA ,RT -PCR测定TNF -αmRNA表达量。 结果 胰岛素、C肽、肿瘤坏死因子、血糖在CPB中和CPB后浓度均显著高于CPB前 ( p <0 .0 1)。与劈胸骨和静脉插管时相比较 ,关胸和缝合房壁时患者TNF -αmRNA表达明显强于相应时点 ( p <0 .0 5 )。 1/ (IxG)与麻醉前相比有显著下降 ( p <0 .0 1)。结论 在CPB心血管手术中存在强烈的应激反应 ,患者表现应激性高血糖。CPB中肿瘤坏死因子明显增高 ,TNF -αmRNA表达明显增加 ,且存在严重的胰岛素抵抗 (Insulinresistance ,IR) 。

OBJECTIVE Investigate the relationship of insulin resistance and expression tumor Necrosis Factor-alpha(TNF-α)mRNA in skeletal muscle and cardiac muscle during cardiopulmonary bypass ( CPB) in cardiovascular surgery. METHODS Blood samples were obtained from 20 patients at the following intervals: before anesthesia, before CPB, after 15 min of CPB, 5 min after declamping of aorta, 20 min after CPB. The concentrations insulin,c-peptide, tumor necrosis factor-alpha (TNF-α) and blood glucose were measured. The insulin-sensitivity index[l/(I x G) ] was obtained. Two gram of the rectus abdominis muscle and cardiac muscle were taken from patients.Total RNA from samples was extracted by trizol template. RT-PCR was used to determine TNF-αmRNA amplification products. RESULTS Insulin, c-peptide, TNF-α were higher during and after ending of CPB than that before starting of CPB (p<0.01). Similar changes in levels of blood glucose. There were significant decrease of 1/(I x G) (p<0.01). CONCLUSION Patients with strong stress exhibited stress hyperglycemia during CPB in cardiovascular surgery. There are an obvious increase of concentrations in tumor necrosis factor-alpha and a deterioration of insulin resistance during CPB. TNF-αmRNA expression was also significantly increased during CPB. Tumor necrosis factor-alpha plays an important role in insulin re-sistance.