糖尿病性高血糖对大鼠缺血性脑损伤的影响

Effect of diabetic hyperglycemia on ischemic brain damage in rats

目的：研究糖尿病性高血糖（ＨＧ）对大鼠缺血性脑损伤的影响。方法：链脲佐菌素引起糖尿病４周的大鼠遭受１０ｍｉｎ前脑缺血，观察脑损伤的病理改变。结果：在海马ＣＡ１和下脚区，ＨＧ组与正常血糖（ＮＧ）组神经元损伤程度相似。然而，ＨＧ组动物有严重的顶叶皮质神经元坏死和“额外脑结构损伤”。结论：糖尿病高血糖大鼠缺血后脑损伤明显加重。

Objective:To explore the effect of diabetic hyperglycemia (HG) on ischemic brain damage in rats.Methods:The rats of streptozotocininduced diabetes suffered from 10 min forebrain ischemia in 4 weeks after the induction of diabetes.Normoglycemic (NG) rats exposed to the same duration of ischemia and shamoperated diabetic rats (Sham) served as control.The animals underwent histopathological analysis of brain damage.Results:In the CA1 and in the subcular regions of hippocampus,the severity and distribution of damage were similar in HG and NG animals.However,HG rats had more severe neuronal necrosis in the parietal cortex,compared with NG animals.In HG rats,additional brain structures were involved besides neuronal damage,e.g.cingulate cortex,thalamus nuclei,substantia nigra pars reticulata (SNPR),and hippocampal CA3 sector,where the neurons were not affected in NG rats subjected at same duration of ischemia.Conclusion:Diabetic hyperglycemia results in exacerbated postischemic brain damage.