Aging impairs the late phase of long-term potentiation at the medial perforant Path-CA3 synapse in awake rats
Aging impairs the late phase of long-term potentiation at the medial perforant Path-CA3 synapse in awake rats
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DOI：
10.1002/syn.20004
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发表时间：
2004-04-01
期刊：
影响因子：
2.3
通讯作者：
Barea-Rodriguez, EJ
中科院分区：
文献类型：
--
作者：
Dieguez, D;Barea-Rodriguez, EJ
衰老对齿状回 (DG) 和 CA1 的长时程增强 (LTP) 的影响已有充分记录，但老年动物内侧穿通路径 (MPP)-CA3 突触的 LTP 仍未被探索。由于 MPP-DG 和 Schaffer-collar-CA1 突触仅占海马突触总数的 20% 左右，因此全球对衰老如何影响海马可塑性的了解仍然有限。人们对海马结构中 LTP 的诱导了解甚多，但调节 LTP 维持的机制却知之甚少，尤其是在衰老过程中。我们研究了衰老对清醒大鼠 MPP-CA3 LTP 诱导和维持的影响。与 DG 和 CA1 的情况一样，高频刺激诱导的 MPP-CA3 突触 LTP 在老年大鼠中是正常的。这些数据表明，老年大鼠 MPP-CA3 突触中 N-甲基-D-天冬氨酸 (NMDA) 受体介导的过程是完整的。相比之下，衰老会在一段时间内损害 MPP-CA3 LTP 的强度和持续时间。此外，这些数据与 CA3 区特别容易受到年龄相关变化的影响的报道一致。我们的数据表明，衰老会损害调节 MPP-CA3 LTP 后期的机制，并有助于更全面地了解衰老如何影响海马可塑性。 (C) 2004 Wiley-Liss, Inc.
The effects of aging on long-term potentiation (LTP) in the dentate gyrus (DG) and CA1 are well documented, but LTP at the medial perforant path (MPP)-CA3 synapse of aged animals has remained unexplored. Because the MPP-DG and Schaffer-collateral-CA1 synapses account for only about 20% of total hippocampal synapses, global understanding of how aging affects hippocampal plasticity has remained limited. Much is known about LTP induction in the hippocampal formation, whereas the mechanisms that regulate LTP maintenance are less understood, especially during aging. We investigated the effects of aging on MPP-CA3 LTP induction and maintenance in awake rats. As is the case in the DG and CA1, high-frequency stimulation-induced LTP at the MPP-CA3 synapse is normal in aged rats. These data indicate that N-methyl-D-aspartate (NMDA) receptor-mediated processes are intact at the MPP-CA3 synapse in aged rats. In contrast, aging impaired the magnitude and duration of MPP-CA3 LTP over a period of days. Also, these data are consistent with reports that area CA3 is especially susceptible to age-related changes. Our data suggest that aging impairs mechanisms that regulate the late phase of MPP-CA3 LTP and contribute to a more global understanding of how aging affects hippocampal plasticity. (C) 2004 Wiley-Liss, Inc.