关键词: 实验性, 海马, 神经元, 细胞凋亡, 细胞周期

Abstract: Objective To explore the changes of hippocampal neuron apoptosi s, cell cycle progression and its related protein expressions in rats with diabe tes mellitus (DM). Methods The male rats were injected intraperitoneally with streptozosin (STZ) to establish DM models. At the end of 12th week, the percentage of the hippocampal neuron apoptosis in the rats suffered from DM was measured with flow cytometry (FCM), and their cell cycle progression was measured with propidium iodide (PI) dying, and their mitochondrial membrane potential was measured with FCM under the Rhodamine 123 dying. The protein expressions of Cyt c and caspase-3 were detected with immunohistochemical methods. Results The diabetic rats developed obviously polydipsia，polyphagia，polyuria and loss of body weight. As compared with the normal controls, the cell percentage of the hippocampal neuron apoptosis in the diabetic rats at the end of the 12th week increased significantly (P<0.05); the cell percentage of G₀/G₁ phase increased significantly (P<0.01), while the cell percentage of S phase decreased significantly (P<0.05); the mitochondrial membrane potential increased significantly (P<0.05), and the expressions of caspase-3 and Cyt c proteins also increased significantly (P<0.05). Conclusion The changes of indices mentioned above may be related to the absence of insulin in diabetic rats caused by hyperglycemia, which might be the reason for the change of hippocampus structure and cognitive function disorder in diabetic rats.

Key words: experimental, hippocampus, neuron, apoptosis, cell cycle