血清真胰岛素、胰岛素原检测在胰岛素抵抗中的应用

Serum true insulin,proinsulin determination and their significances in insulin resistance

目的:探讨不同糖耐量人群血清真胰岛素(TI)、胰岛素原(PI)变化的特点及其在评价胰岛β细胞功能和胰岛素抵抗(IR)方面的应用。方法:按空腹血糖与口服葡萄糖耐量试验结果分为糖耐量正常组(NGT)、糖耐量减低组(IGT)及2型糖尿病组(T2DM)各60例,各组应用放射免疫分析(RIA)法分别测定空腹免疫反应性胰岛素(IRI)、TI、PI。采用稳态模式评估法(Homa)计算胰岛β细胞功能指数(Homa-β)和胰岛素抵抗指数(Homa-IR),并进行分析。结果:空腹IRI和TI的变化为IRI值在DM组和IGT组低于NGT组(P<0.05);TI值DM组<IGT组<NGT组(P<0.05)。β细胞功能指数由IRI计算Homa-βIRI,在DM组和IGT组低于NGT组(P<0.05);由TI计算的Homa-βTI值,不仅DM组和IGT组低于NGT组(P<0.05),DM组也低于IGT组(P<0.05)。胰岛素抵抗指数无论是用TI还是用IRI计算的Homa-IR均显示DM组>IGT组>NGT组(P<0.05)。TI/IRI的比值DM组<IGT组<NGT组(P<0.05);空腹PI值DM组高于IGT组和NGT组(P<0.05),PI/IRI比值DM组>IGT组>NGT组。结论:血清IRI和TI水平均可用于计算胰岛素抵抗,TI/IRI比值是反映β细胞功能的良好指标,特别是临床判断T2DM患者的病情发展和指导药物治疗有重要的临床意义。

Objective： To study the changes of true insulin （TI） and proinsulin（PI） in subjects with NGT, IGT and DM;To study the significances of TI and PI in evaluating β-cell function, insulin resistance （IR）. Methods： The levels of serum TI, PI, IRI were determined by radioimmunoassay（RIA） in 60 cases with type 2 diabetes mellitus （T2DM）, 60 cases with impaired glucose tolerance （Group IGT） and 60 cases with normal glucose tolerance （Group NGT）. The insulin resistance index （Homa-IR） and pancreatic β cell function index （Homa-β）were calculated and analyzed with Homeostasis Model Assessment （Homa）. Results： The fasting IRI level in DM group was lower than that in NGT （P〈0.05） .The fasting IRI level in IGT group was lower than that in NGT group（P〈0.05）;The fasting TI levels in DM group was lower than that in IGT（P〈0.05） and NGT（P〈0.05） groups. The pancreatic β cell function index（Homa-βIRI）of IRI in DM and IGT groups were lower than that in NGT group （P〈0.05）.The pancreatic β cell function index （Homa- BTI,） of TI in DM and IGT groups were lower than that in NGT group （P〈0.05）.The pancreatic β cell function index （Homa-BTI） of TI in DM group was lower than that in IGT group （P〈0.05） too. The insulin resistance index（Homa-IR） of IRI and TI both showed that DM group was higher than IGT group （P〈0.05）, and IGT group was higher than NGT group （P〈0.05）. The ratio of TI/IRI in DM and IGT groups were lower than that in NGT group（P〈0.05）.The ratio of TI/IRI in IGT group was lower than that in NGT group（P〈0.05）. The fasting PI level in DM group was higher than that in IGT group （P〈0.05） and NGT group （P〈0.05）. The ratio of PI/IRI in DM group was higher than that in IGT group（P〈0.05） and NGT group（P〈0.05）.The ratio of PI/IRI in IGT group was higher than that in NGT group （P〈0.05）. Conclusion： The level of IRI and TI in serum can be used to calculate the resistance of insulin. The ratio of TI/IRI is a good marker in evaluating β-cell function and is important for judging the development of type 2 DM.