The effect of hyperglycaemia on the islet β-cell responsiveness in type 2 diabetic patients

目的了解葡萄糖毒性对胰岛β细胞分泌功能的影响. 方法观察118例2型糖尿病(T2DM)患者在不同血糖状态下,胰岛β细胞分泌对口服葡萄糖耐量试验(OGTT)和胰高血糖素刺激试验(GST)的反应能力. 结果胰岛β细胞的分泌功能在OGTT随空腹血糖的升高而下降(P<0.01);在GST随血糖升高而增强,达9 mmol/L以上时维持在高水平.OGTT胰岛素释放倍数与胰岛素抵抗指数(HOMA-IR)呈负相关(P<0.01),GST胰岛素释放倍数与胰岛β细胞功能指数(HOMA-β)呈正相关(P<0.01). 结论葡萄糖毒性干扰胰岛β细胞功能的判断,血糖过高抑制OGTT时的胰岛素释放,GST受此影响小,能较客观反映胰岛β细胞功能状态.Objective To evaluate the effect of chronic hyper glycaemia on the pancreatic β-cell response in diabetic patients. Me thods We investigated the effect of various blood glucose levels on the β-cell response to stimulation with a standard oral glucose or intravenous gl ucagon in 118 patients with type 2 diabetes. Results The rele ases of C-peptide and insulin were decreased with increased level of fasting blood glucose (P<0.01)after oral glucose stimulation, and were increased with decreased levels of fasting blood glucose after glucagon stimulation wh ile C-peptide and insulin release keeping higher when fasting blood glucose lev el was above 9 mmol/L. The release of insulin showed an inverse association to HOMA-IR (P<0.01)after oral glucose stimulation and it showed a positive association with HOMA-β(P<0.01)after glucagon stimulation. C onclusions The evaluation of function of β-cell secretion is confused by glucose toxicity because severe hyperglycaemia significantly reduces C-pep tide and insulin release after oral glucose stimulation, but this is not the cas e after glucagon stimulation in type 2 diabetic patients.中国科学引文数据库(CSCD)04235-2371