Institute II for Anatomy, Medical Faculty, University of Cologne, Cologne, Germany.
Department of Psychiatry and Neuropsychology, Faculty of Health, Medicine and Life Sciences, European School of Neuroscience (EURON), Maastricht University, Maastricht, The Netherlands;
Curr Neuropharmacol. 2014 Jan;12(1):37-43. doi: 10.2174/1570159X113119990045.
The purines ATP and adenosine are widely recognized for their neuromodulatory effects. They have been shown to have effects on neurons via various receptors and interactions with glial cells. In particular, long-term potentiation (LTP) in hippocampal slice preparations has been found to be modulated by ATP and adenosine. This review gives an overview of purinergic signaling in relation to hippocampal LTP and memory formation. The data supports the hypothesis that adenosine mediates a tonic suppression of synaptic transmission. Thus, low adenosine levels appear to increase basal synaptic activity via a decreased activation of the inhibitor A1 receptor, consequently making it more difficult to induce LTP because of lower contrast. During high stimulation, the inhibition of neighboring pathways by adenosine, in combination with an A2a receptor activation, appears to increase contrast of excited pathways against a nonexcited background. This would enable amplification of specific signaling while suppressing non-specific events. Although a clear role for purinergic signaling in LTP is evident, more studies are needed to scrutinize the modulatory role of ATP and adenosine and their receptors in synaptic plasticity and memory.
嘌呤核苷酸 ATP 和腺苷以其神经调质作用而被广泛认可。它们通过各种受体和与神经胶质细胞的相互作用对神经元产生影响。特别是，已经发现海马切片制备中的长时程增强（LTP）受到 ATP 和腺苷的调节。这篇综述概述了与海马体 LTP 和记忆形成有关的嘌呤能信号传递。这些数据支持了这样的假设，即腺苷通过抑制性 A1 受体的减少激活来介导突触传递的紧张性抑制。因此，由于对比度降低，低腺苷水平似乎通过降低基础突触活动来增加基础突触活动，从而更难以诱导 LTP。在高刺激期间，腺苷对相邻途径的抑制作用与 A2a 受体的激活相结合，似乎会增加兴奋途径与无兴奋背景之间的对比度。这将能够在抑制非特异性事件的同时放大特定信号。尽管嘌呤能信号传递在 LTP 中的作用是明确的，但仍需要更多的研究来仔细研究 ATP 和腺苷及其受体在突触可塑性和记忆中的调节作用。
