Objective: To prepare an apoptosis cell model of Alzheimer Disease (AD) by PC-12 cells treated with β-amyloid protein (Aβ). Methods: PC-12 cells were incubated with different concentrations of Aβ25-35 for different...Objective: To prepare an apoptosis cell model of Alzheimer Disease (AD) by PC-12 cells treated with β-amyloid protein (Aβ). Methods: PC-12 cells were incubated with different concentrations of Aβ25-35 for different duration in vitro. The cell viability was detected by MTT assay. Morphological features of apoptosis were analyzed, with Hoechst 33258/ Propidium iodide dual staining, The level of intracellular free calcium ([Ca2+]i) was calculated by Fura-2/AM fluorescence ratio imaging. Results: ① The viability of PC-12 cells was significantly decreased in proportion to concentration of Aβ25-35 and duration of exposure to Aβ25-35. ② The apoptotic cells appeared in a time and concentration-dependent manner, and the maximal apoptosis happened at 48 h after exposure to 20 μmol/L of Aβ25-35 and 36 h to 30 μmol/L, Cell death reached the peak at 12-24 h later than the apoptotic peak. (3) [Ca2+]i of PC-12 cells was increased in proportion to duration of exposure to the same concentration of Aβ25-35. The time of the highest increase rate of [Ca2+]i was about 12 h earlier than that of apoptosis. Conclusion: An AD cell model using the PC-12 cells induced with Aβ25-35 displays a series of changes related to apoptosis, which may be related to elevation of [Ca2+]i.展开更多
目的:探讨海马内注射β-amyloid protein 25-35(Aβ25-35)所致Alzheizer’s病(AD)模型大鼠空间学习记忆功能障碍的海马突触可塑性长时程增强(LTP)机制,为联合开展AD动物行为学和在体电生理学研究提供实验证据。方法:在脑立体定位仪上给...目的:探讨海马内注射β-amyloid protein 25-35(Aβ25-35)所致Alzheizer’s病(AD)模型大鼠空间学习记忆功能障碍的海马突触可塑性长时程增强(LTP)机制,为联合开展AD动物行为学和在体电生理学研究提供实验证据。方法:在脑立体定位仪上给予大鼠双侧海马分别注射4 nmol/L Aβ25-35或等体积生理盐水每侧2μl,手术后恢复2周,每只大鼠依次进行行为学和电生理两部分实验。首先,利用Morris水迷宫进行空间学习、记忆功能测试;之后,进行在体海马CA1区场兴奋性突触后电位(fEPSP)引导记录实验,观察突触可塑性指标长时程增强(LTP)的改变。结果:与对照组相比,海马内注射Aβ25-35大鼠的空间学习记忆功能和在体海马突触可塑性LTP均有改变,其中:逃避潜伏期和逃避距离明显增加(P<0.01);目标象限内游泳时间和距离明显缩短(P<0.01);在体海马LTP幅度显著降低(P<0.01)。结论:海马内注射Aβ25-35可导致大鼠空间学习记忆功能障碍;联合实验中Aβ25-35同样可引起在体海马LTP改变。提示同批动物先后进行行为学和电生理学测试的方法是可行的,行为学实验不会影响后续LTP的实验结果。因此,本实验为行为学改变后进行在体LTP机制探讨提供了实验依据,为有效开展行为学和电生理学实验提供了思路。展开更多
基金Supported by Grant from the National Natural Science Foundation of China(39880008)the Natural Science Foundation of Shaanxi Province(98sm61)
文摘Objective: To prepare an apoptosis cell model of Alzheimer Disease (AD) by PC-12 cells treated with β-amyloid protein (Aβ). Methods: PC-12 cells were incubated with different concentrations of Aβ25-35 for different duration in vitro. The cell viability was detected by MTT assay. Morphological features of apoptosis were analyzed, with Hoechst 33258/ Propidium iodide dual staining, The level of intracellular free calcium ([Ca2+]i) was calculated by Fura-2/AM fluorescence ratio imaging. Results: ① The viability of PC-12 cells was significantly decreased in proportion to concentration of Aβ25-35 and duration of exposure to Aβ25-35. ② The apoptotic cells appeared in a time and concentration-dependent manner, and the maximal apoptosis happened at 48 h after exposure to 20 μmol/L of Aβ25-35 and 36 h to 30 μmol/L, Cell death reached the peak at 12-24 h later than the apoptotic peak. (3) [Ca2+]i of PC-12 cells was increased in proportion to duration of exposure to the same concentration of Aβ25-35. The time of the highest increase rate of [Ca2+]i was about 12 h earlier than that of apoptosis. Conclusion: An AD cell model using the PC-12 cells induced with Aβ25-35 displays a series of changes related to apoptosis, which may be related to elevation of [Ca2+]i.
文摘目的:探讨海马内注射β-amyloid protein 25-35(Aβ25-35)所致Alzheizer’s病(AD)模型大鼠空间学习记忆功能障碍的海马突触可塑性长时程增强(LTP)机制,为联合开展AD动物行为学和在体电生理学研究提供实验证据。方法:在脑立体定位仪上给予大鼠双侧海马分别注射4 nmol/L Aβ25-35或等体积生理盐水每侧2μl,手术后恢复2周,每只大鼠依次进行行为学和电生理两部分实验。首先,利用Morris水迷宫进行空间学习、记忆功能测试;之后,进行在体海马CA1区场兴奋性突触后电位(fEPSP)引导记录实验,观察突触可塑性指标长时程增强(LTP)的改变。结果:与对照组相比,海马内注射Aβ25-35大鼠的空间学习记忆功能和在体海马突触可塑性LTP均有改变,其中:逃避潜伏期和逃避距离明显增加(P<0.01);目标象限内游泳时间和距离明显缩短(P<0.01);在体海马LTP幅度显著降低(P<0.01)。结论:海马内注射Aβ25-35可导致大鼠空间学习记忆功能障碍;联合实验中Aβ25-35同样可引起在体海马LTP改变。提示同批动物先后进行行为学和电生理学测试的方法是可行的,行为学实验不会影响后续LTP的实验结果。因此,本实验为行为学改变后进行在体LTP机制探讨提供了实验依据,为有效开展行为学和电生理学实验提供了思路。
