Deupree D L, Bradley J, Turner D A
Department of Surgery (Neurosurgery), Duke University Medical Center, Durham, NC 27710.
Neurobiol Aging. 1993 May-Jun;14(3):249-58. doi: 10.1016/0197-4580(93)90009-z.
F344 rats of various ages (2-3 months, 15-16 months, and 24-25 months) were tested on a spatial memory task. The 15- and 24-month-old rat groups showed impaired acquisition and retention of the memory task, compared to the young animals. Extracellular field potential recordings in the CA1 region were subsequently performed in vitro, using hippocampal slices from both these tested rats and similar but untested F344 young and aged rats. Findings included: a) a positive correlation between baseline dendritic EPSP slope values and retention scores across age groups; b) a more rapid decay of both somatic and dendritic short-term potentiation in aged slices; c) decreased somatic but not dendritic long-term potentiation overall in aged slices, regardless of bath Mg2+ level; and d) decreased paired-pulse facilitation in slices from aged rats bathed in 4.0 mM Mg2+ media compared to young controls. These findings suggest an age-related alteration in both presynaptic and postsynaptic potentiation mechanisms, which may relate to the poor spatial memory acquisition and retention in the aged rats. These age-related differences point to substantial changes in neuronal signal processing capabilities and local circuit function in the hippocampus as a function of aging.
对不同年龄（2 - 3个月、15 - 16个月和24 - 25个月）的F344大鼠进行了空间记忆任务测试。与年轻大鼠相比，15个月和24个月龄的大鼠组在记忆任务的获取和保持方面表现受损。随后，使用这些受试大鼠以及相似但未受试的F344年轻和老龄大鼠的海马切片，在体外进行了CA1区域的细胞外场电位记录。研究结果包括：a）各年龄组基线树突状兴奋性突触后电位（EPSP）斜率值与保持分数之间呈正相关；b）老龄切片中体细胞和树突状短期增强均衰减更快；c）老龄切片中总体体细胞长期增强降低，但树突状长期增强未降低，无论浴槽中镁离子（Mg2+）水平如何；d）与年轻对照组相比，在4.0 mM Mg2+培养基中培养的老龄大鼠切片中配对脉冲易化作用降低。这些发现表明，突触前和突触后增强机制均存在与年龄相关的改变，这可能与老龄大鼠空间记忆获取和保持能力差有关。这些与年龄相关的差异表明，随着年龄增长，海马体中神经元信号处理能力和局部回路功能发生了显著变化。
