Department of Pharmacology, Qingdao University School of Pharmacy, Qingdao, China.
Department of Neurology, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.
Mol Pain. 2023 Jan-Dec;19:17448069231179011. doi: 10.1177/17448069231179011.
Synaptic plasticity such as Long-term potentiation (LTP) is a key mechanism for learning in central synapses including the cortex. There are two least two major forms of LTPs: presynaptic LTP and postsynaptic LTP. For postsynaptic LTP, the potentiation of AMPA receptor-mediated responses through protein phosphorylation is thought to be a key mechanism. Silent synapses have been reported in the hippocampus, but it is thought to be mainly present in the cortex during early development, and may contribute to maturation of the cortical circuit. However, recent several lines of evidence demonstrate that silent synapses may exist in mature synapses of adult cortex, and they can be recruited by LTP-inducing protocols, as well as chemical-induced LTP. In pain-related cortical regions, silent synapses may not only contribute to cortical excitation after peripheral injury, but also the recruitment of new cortical circuits as well. Thus, it is proposed that silent synapses and modification of functional AMPA receptors and NMDA receptors may play important roles in chronic pain, including phantom pain.
突触可塑性，如长时程增强（LTP），是中枢突触（包括皮层）学习的关键机制。有两种主要的 LTP 形式：突触前 LTP 和突触后 LTP。对于突触后 LTP，通过蛋白质磷酸化增强 AMPA 受体介导的反应被认为是一种关键机制。已经在海马体中报道了沉默突触，但据认为它主要存在于皮质发育早期，可能有助于皮质回路的成熟。然而，最近有几条证据表明，沉默突触可能存在于成年皮质的成熟突触中，并且可以通过诱导 LTP 的方案以及化学诱导的 LTP 来招募它们。在与疼痛相关的皮质区域，沉默突触不仅可能有助于外周损伤后的皮质兴奋，还可能招募新的皮质回路。因此，有人提出，沉默突触以及功能性 AMPA 受体和 NMDA 受体的修饰可能在慢性疼痛（包括幻痛）中发挥重要作用。
