Effects of L-DOPA on quadripulse magnetic stimulation-induced long-term potentiation in older adults. Neurobiology of Aging 84: 217-224, 2019
Effects of L-DOPA on quadripulse magnetic stimulation-induced long-term potentiation in older adults. Neurobiology of Aging 84: 217-224, 2019
复制标题
左旋多巴对老年人四脉冲磁刺激引起的长时程增强的影响。
DOI：
10.1016/j.neurobiolaging.2019.08.005
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
Hanajima R
中科院分区：
文献类型：
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作者：
Tanaka N;Tsutsumi R;Shirota Y;Shimizu T;Ohminami S;Terao Y;Ugawa Y;Tsuji S;Hanajima R
先前曾报道，与年轻人相比，老年人的皮质可塑性降低。然而，多巴胺对这种可塑性降低的影响仍然未知。在这里，我们评估了高剂量（200 mg）和中剂量（100 mg）L-3,4-二羟基苯丙氨酸（L-DOPA）摄入量对老年人（约 65 岁）四脉冲磁刺激 (QPS) 诱导的长时程增强 (LTP) 样效应的影响。受试者为 32 名（200 毫克）和 20 名（100 毫克）健康老年志愿者。这项研究被设计为针对一剂左旋多巴的双盲、交叉和安慰剂对照试验。服用 L-DOPA 或安慰剂药物两小时后，将 QPS 应用于运动皮层。记录运动诱发电位以评估运动皮质兴奋性变化。我们发现，两种剂量的 L-DOPA 均可增强老年人 QPS 后的 LTP。我们将受试者分为 QPS 响应者和 QPS 无响应者。两种 L-DOPA 剂量均在 QPS 无应答者中产生显着的 LTP 增强，而任一剂量均未在 QPS 应答者中产生显着的 LTP 增强。总的来说，我们的研究结果表明，多巴胺可以部分改善老年人中观察到的神经可塑性降低。
Reduced cortical plasticity has been previously reported in older adult as compared with young adults. However, the effects of dopamine on this plasticity reduction remain unknown. Here, we assessed the effects of high-dose (200 mg) and medium-dose (100 mg) L-3,4-dihydroxyphenylalanine (L-DOPA) intake on the long-term potentiation (LTP)-like effect induced by quadripulse magnetic stimulation (QPS) in older adults (aged ∼65 years). The subjects were 32 (200 mg) and 20 (100 mg) healthy older adult volunteers. This study was designed as a double-blind, crossover and placebo-controlled trial on one dose of L-dopa. Two hours after taking L-DOPA or placebo-drug, QPS was applied over the motor cortex. Motor evoked potentials were recorded to evaluate the motor cortical excitability changes. We found that both doses of L-DOPA enhanced LTP after QPS in older adults as one group. We classified subjects into QPS responders and QPS nonresponders. Both L-DOPA doses produced significant LTP enhancement in QPS nonresponders, whereas either of doses did not produce significant LTP enhancement in QPS responders. Collectively, our findings suggest that the neural plasticity reductions observed in older adults could be partly improved by dopamine.