Dietary cholesterol concentration affects synaptic plasticity and dendrite spine morphology of rabbit hippocampal neurons.
Dietary cholesterol concentration affects synaptic plasticity and dendrite spine morphology of rabbit hippocampal neurons.
复制标题
DOI：
10.1016/j.brainres.2015.06.049
复制
发表时间：
2015-10-05
期刊：
影响因子：
2.9
通讯作者：
Zheng W
中科院分区：
文献类型：
--
作者：
Wang D;Zheng W
先前的研究表明，饮食中的胆固醇可以提高学习能力，但延缓记忆，这可能部分是由于海马区胆固醇水平增加和海马区CA1区神经元后超极化(AHP)幅度降低所致。本研究探讨了膳食胆固醇对兔海马CA1区神经元突触可塑性和脊髓形态的剂量依赖性影响，突触后结构负责突触可塑性。场电位记录显示，低浓度的饮食胆固醇增加了长时程增强(LTP)的表达，而高浓度则显著降低了LTP的表达。饮食中的胆固醇促进了基础突触传递，但不影响突触前功能。DiI染色显示，饮食中胆固醇诱导的树突棘形态发生改变，表现为蘑菇棘密度增加和细刺密度降低，这两种树突棘可能与记忆巩固和学习获得有关。饮食中的胆固醇也影响了蘑菇刺的几何尺寸。因此，饮食胆固醇呈剂量依赖性地调节海马CA1区神经元的突触可塑性和树突棘形态，这些形态可能介导先前被认为是喂养胆固醇饮食导致的学习和记忆变化。
Previous studies have shown dietary cholesterol can enhance learning but retard memory which may be partly due to increased cholesterol levels in hippocampus and reduced afterhyperpolarization (AHP) amplitude of hippocampal CA1 neurons. This study explored the dose-dependent effect of dietary cholesterol on synaptic plasticity of rabbit hippocampal CA1 neurons and spine morphology, the postsynaptic structures responsible for synaptic plasticity. Field potential recordings revealed a low concentration of dietary cholesterol increased long-term potentiation (LTP) expression while high concentrations produced a pronounced reduction in LTP expression. Dietary cholesterol facilitated basal synaptic transmission but did not influence presynaptic function. DiI staining showed dietary cholesterol induced alterations in dendrite spine morphology characterized by increased mushroom spine density and decreased thin spine density, two kinds of dendritic spines that may be linked to memory consolidation and learning acquisition. Dietary cholesterol also modulated the geometric measures of mushroom spines. Therefore, dietary cholesterol dose-dependently modulated both synaptic plasticity and dendrite spine morphologies of hippocampal CA1 neurons that could mediate learning and memory changes previously seen to result from feeding a cholesterol diet.