中文摘要：

目的研究大鼠在患1型和2型糖尿病后，对在体海马前穿通纤维-齿状回通路（PP—DG）的突触可塑性造成的影响。方法将70只SD大鼠（180±20）g随机分成3组：对照组、1型糖尿病模型组、2型糖尿病模型组。在水迷宫测试后，在每个模型组中选出空间记忆能力较差的15只大鼠，研究糖尿病引起的海马PP-DG通路双脉冲易化（PPF）、长时程增强（LTP）等突触可塑性的变化。结果大鼠在患1型和2型糖尿病后，与对照组相比，海马LTP的形成均被显著抑制（P〈0．05），并且1型糖尿病对LTP的抑制作用更大；糖尿病抑制了海马PPF的幅度（P〈0．05），并减小了PPF的易化宽度。结论1型和2型糖尿病对大鼠海马PP．DG通路的突触可塑性造成了破坏，这与之前水迷宫行为学测试的结果相对应。

英文摘要：

Objective To study the effects of diabetes on hippocampal synaptic plasticity in perforant path-dentate gyms pathway （PP-DG） in rats. Methods 70 SD rats （180±20） g were divided into 3 groups at random： control group, type l diabetes group （DM 1 ）and type2 diabetes group （DM2）. After Morris water maze test, 15 rats that showed worse spatial memory ability were selected in each model group to investigate the variation of paired-pulse facilitation （PPF） and the range of synaptic plasticity. Field potentials were recorded in the dentate gyrus of the dorsal hippocampus by stimulating the perforant path. Results Contrast to the control group, diabetic rats＇ hippocampal LTP were depressed （P〈0.05）, and typel diabetic rats＇ LTP reduced much more. Diabetic rats＇ PPF ratio was reduced contrast to the control group （P〈0.05）. Conclusion Typel and type2 diabetes impaired synaptic plasticity of hippocampal PP-DG pathway in rats, which conformed the results of water maze test.