Kavalali Ege T
Vanderbilt Brain Institute and the Department of Pharmacology, Vanderbilt University, Nashville, TN, 37240-7933, USA.
J Physiol. 2020 May;598(9):1649-1654. doi: 10.1113/JP276541. Epub 2019 Feb 27.
Action potential driven neuronal signalling drives several electrical and biochemical processes in the nervous system. However, neurons can maintain synaptic communication and signalling under resting conditions independently of activity. Importantly, these processes are regulated by Ca signals that occur at rest. Several studies have suggested that opening of voltage-gated Ca channels near resting membrane potentials, activation of NMDA receptors in the absence of depolarization or Ca release from intracellular stores can drive neurotransmitter release as well as subsequent signalling in the absence of action potentials. Interestingly, recent studies have demonstrated that manipulation of resting neuronal Ca signalling yielded pronounced homeostatic synaptic plasticity, suggesting a critical role for this resting form of signalling in regulation of synaptic efficacy and neuronal homeostasis. Given their robust impact on synaptic efficacy and neuronal signalling, neuronal resting Ca signals warrant further mechanistic analysis that includes the potential role of store-operated Ca entry in these processes.
动作电位驱动的神经元信号传导在神经系统中驱动多种电和生化过程。然而，神经元可以在静息条件下独立于活动维持突触通信和信号传导。重要的是，这些过程受静息时发生的钙信号调节。多项研究表明，在静息膜电位附近电压门控钙通道的开放、在无去极化情况下NMDA受体的激活或细胞内钙库的钙释放，均可在无动作电位时驱动神经递质释放及后续信号传导。有趣的是，最近的研究表明，对静息神经元钙信号的操纵产生了显著的稳态突触可塑性，表明这种静息形式的信号传导在调节突触效能和神经元稳态中起关键作用。鉴于它们对突触效能和神经元信号传导有强大影响，神经元静息钙信号值得进行进一步的机制分析，包括钙库操纵性钙内流在这些过程中的潜在作用。
