链脲佐菌素小鼠糖尿病胰岛结构改变的定量病理学测试及分析

Quantitative pathological test and analysis of structural changes of islets in streptozotocin-induced diabetic mice

目的:定量揭示链脲佐菌素(Streptozotocin,STZ)诱发的小鼠糖尿病胰岛结构改变的特点,为分析胰岛功能改变补充定量病理学基础。方法:腹腔注射STZ,诱发Balb/c小鼠糖尿病;过量CO_(2)处死小鼠并取胰腺,常规病理制样、胰岛素免疫组化染色、图像测试及定量分析。结果:造模第8周,糖尿病组(DM组)小鼠血糖显著高于正常对照组(NC组)小鼠,DM组小鼠血糖均值为19.3 mmol/L;相比NC组小鼠,DM组小鼠胰岛数目、β细胞数目及面积显著减少(P<0.05),计算得出β细胞数量丧失约62.7%,胰岛β细胞面积丧失约27.0%,胰岛素阳性单位(PU值)表达减少约53.8%。DM组小鼠胰岛β细胞面积密度(A_(Aβ,PI))、面数密度(N_(Aβ,PI))、数量百分比(β_(Per))均显著降低(P<0.05),其中PU值、A_(Aβ,PI)、β_(Per)与血糖升高呈负相关,皮尔森相关系数(R值)分别为-0.653、-0.736和-0.899(显著性均<0.05);建立造模时间(t)与胰岛β细胞数量百分比改变的函数:β_(Per)(%)=79.68-9.74t+0.38t^(2)+0.06t^(3)-4.66×10^(-3)t^(4)+2.86×10^(-5)t^(5)+1.68×10^(-5)t^(6)。结论:通过定量病理学技术测量糖尿病小鼠模型胰岛和β细胞形态学改变的相关指标,能够帮助准确评估胰岛的损伤情况,并建立血糖变化和所测量数值的相关数学模型,用以预测血糖升高导致胰岛损伤的具体情况。

Objective To quantitatively reveal the structural changes of pancreatic islets in mice with streptozotocin-induced diabetes,and to provide a pathological basis for the analysis of changes in islet function.Methods Intraperitoneal injection of streptozotocin(STZ)induced diabetes in Balb/c mice.After the mice were sacrificed by excessive CO_(2),the pancreas tissues were taken for routine pathological sample preparation,insulin immunohistochemical staining,image test and quantitative analysis.Results At the 8th week of modeling,the blood glucose of diabetic group(DM group)was significantly higher than that of normal group(NC group),and the mean blood glucose of DM group was 19.3 mmol/L.Compared with NC group,DM group had less islets,fewer β cells and reduced β cell area(P<0.05),and it was calculated that β cell count,β cell area,and the expression of positive unit of insulin were decreased by 62.7%,27.0%,and 53.8%,respectively.The area density(A_(Aβ,PI)),numerical density(N_(Aβ,PI))and number percentage(β_(Per))of pancreatic β cells in DM group were significantly decreased(P<0.05).PU,A_(Aβ,PI) and β_(Per) were negatively correlated with the rise of blood glucose,with Pearson correlation coefficients(R value)of-0.653,-0.736 and-0.899,respectively(P<0.05).Moreover,a function of modeling time(t)and the percentage change of pancreatic β cell count was established:β_(Per)(%)=79.68-9.74t+0.38t^(2)+0.06t3-4.66×10^(-3)t^(4)+2.86×10^(-5)t^(5)+1.68×10^(-5)t^(6).Conclusion Measuring the indicators related to the morphological changes ofβcells and the pancreatic islets and in diabetic mice models using quantitative pathological technique can help accurately evaluate the damage of pancreatic islets,and establish the mathematical model of blood glucose and the measured values for predicting the damage of pancreatic islets caused by the rise of blood glucose.