摘要
目的 :探讨严重烫伤后胰岛素信号在肝细胞转导缺陷的环节 ,以阐明严重烫伤后肝脏胰岛素抵抗的发生机制。方法 :以 30 %体表面积背部皮肤全层 (Ⅲ度 )烫伤大鼠为模型 ,采用WGA -Sepharose 4B亲和层析技术部分纯化大鼠肝细胞胰岛素受体 ,通过胰岛素受体结合实验、受体蛋白γ - 32 P -ATP自身磷酸化SDS -聚丙烯酰胺凝胶电泳 (SDS-PAGE)放射自显影和外源性底物磷酸化 ,观察烫伤大鼠早期肝细胞胰岛素受体结合行为、受体 β -亚基自身磷酸化和受体酪氨酸蛋白激酶 (TPK)活性的变化。结果 :严重烫伤大鼠伤后 3d肝细胞胰岛素受体最大结合容量及亲和力无明显改变 ;但受体 β-亚基自身磷酸化能明显下降 ;受体TPK活性亦明显降低并对胰岛素刺激的反应性明显减退。 结论 :严重烫伤后胰岛素信号在肝细胞转导发生偶联障碍 。
Objective:To clarify the site of transduction defects of insulin signal in rat liver and the mechanism of insulin resistance after severely scalded.Methods:In the rats inflicted 30% TBSA Ⅲ scalding,the insulin receptors of rat hepatocytes were partially purified by WGA-Sepharose 4B affinity chromatography The binding ability of insulin receptor to insulin was determined by 125 I insulin binding test The changes of autophosphorylation of insulin receptor β-subunit and the activity of TPK of insulin receptor were observed by SDS-PAGE autoradiography of phosphorylation of insulin receptors and phosphorylation of exogenous substrate Results:The maximum binding capacity and affinity of insulin receptor to insulin did not markedly changed,but the degree of autophosphorylation of insulin receptor β-subunit and the activity of TPK of insulin receptor and its sensitivity to insulin stimulation in the liver were significantly decreased as compared with the controls Conclusion:The defects of insulin receptor signal transduction in the liver may be the molecular mechanism of insulin resistance in severely scalded rats.
出处
《西南国防医药》
CAS
2003年第2期129-132,共4页
Medical Journal of National Defending Forces in Southwest China
