不同血糖水平人群胰岛β细胞功能的变化

Change of islet β-cell function in people with different blood glucose levels

目的 探讨不同血糖水平人群胰岛 β细胞功能的变化以及不同浓度葡萄糖对胰岛素分泌功能的影响。方法 2 2 6例受试者根据口服葡萄糖耐量试验 (OGTT) 2小时血糖 (PPG)分为 5组 ,第 1组 :PPG <7.8mmol/L ;第 2组 :7.8≤PPG <11.1mmol/L ;第 3组 :11.1≤PPG <14 .0mmol/L ;第 4组 :14 .0≤PPG <16 .0mmol/L ;第 5组 :PPG >16 .0mmol/L。受试者行OGTT和胰岛素释放试验 ,计算Homaβ细胞功能指数 (HBCI)、糖负荷 30分钟胰岛素增值与30分钟血糖增值的比值 (ΔI3 0 /ΔG3 0 )及胰岛素曲线下面积 (INSAUC)。结果 ①当PPG <14mmol/L时 ,随着PPG升高 ,空腹胰岛素 (FINS)水平逐渐上升 ,OGTT 2小时胰岛素 (PINS)开始随着PPG升高而升高 ,当PPG >14mmol/L时明显降低 (P <0 .0 5 )。②随着血糖水平升高 ,HBCI和ΔI3 0 /ΔG3 0 呈依次降低趋势 ;INSAUC在第 2组达到高峰 ,其后随着血糖升高而呈下降趋势。结论 较低浓度葡萄糖促进胰岛素分泌 ,当PPG >14mmol/L时高浓度葡萄糖抑制胰岛素分泌 ,表现出葡萄糖毒性作用。随着血糖水平升高 ,胰岛 β细胞功能逐渐减退。

Objective To study the changes of islet β-cell function and the effects of different plasma glucose levels on insulin secretion function in subjects with different blood glucose levels. Methods Two hundred and twenty-six subjects were divided into five groups by 2 h postprandial plasma glucose(PPG),the first group, PPG< 7.8 mmol/L, the second group, 7.8≤PPG< 11.1 mmol/L, the third group, 11.1≤PPG< 14.0 mmol/L, the fourth group, 14.0≤PPG< 16.0 mmol/L, the fifth group, PPG>16.0 mmol/L. Oral glucose tolerance test(OGTT) and insulin release test were conducted in 226 subjects, then Homa β-cell function index(HBCI), ΔI 30/ΔG 30 and insulin area under curve(INS AUC) were calculated. Results ①Among the subjects with PPG<14 mmol/L, FINS was elevated gradually with plasma glucose;PINS was elevated gradually with PPG<14 mmol/L;but PINS decreased significantly after PPG>14 mmol/L.②HBCI and ΔI 30/ΔG 30 were decreased gradually while PPG was elevating. INS AUC in the second group was the highest among five groups,then it was decreased gradually with elevated plasma glucose. Conclusion Lower concentration of glucose stimulates insulin secretion, plasma insulin concentration decreases significantly after PPG>14 mmol/L, which indicates the effects of glucose toxicity. Islet β-cell function was decreased gradually with elevated plasma glucose.