Uchida Tsutomu, Shimada Koichiro, Tanabe Ryutaro, Kubota Tatsuya, Ito Daisuke, Yamazaki Kenji, Gohara Kazutoshi
Division of Applied Physics, Faculty of Engineering, Hokkaido University, N13 W8 Kita-ku, Sapporo, Hokkaido 062-8628, Japan.
IBRO Rep. 2017 Sep 8;3:45-54. doi: 10.1016/j.ibror.2017.09.001. eCollection 2017 Dec.
Mature rat cortical neuronal networks cultured on multi-electrode arrays (MEAs) are known to show spontaneous synchronized bursts accompanied by independent single spikes. The spontaneous synchronized bursts can be inhibited by Xe gas. In this study, we adjust the Xe gas pressure to control the amount of Xe in a neuron-cultured MEA medium. We show that the synchronized bursts cease completely within several minutes by applying Xe gas at partial pressures above 0.3 MPa. After depressurizing and purging with fresh air, the synchronized bursts recover to their original frequency. Thus, we confirmed that Xe acts as a network-activity inhibitor of the cultured neuronal network on MEAs. But below 0.3 MPa, the synchronized bursts are inhibited only partially, depending on the Xe partial pressure. Based on the partial-pressure influence on the change of the neuronal network activities, we find the critical concentration of Xe for the inhibition effect to be approximately 9.5 mM, a value above which more than 90% of the synchronized burst activity is inhibited. Further systematic observations with Xe-air mixed gases show that pressurized air with a small amount of Xe suppresses the inhibition of synchronized bursts, suggesting an air component that can accelerate the synchronized bursts.
已知在多电极阵列（MEA）上培养的成熟大鼠皮质神经元网络会显示出自发性同步爆发，并伴有独立的单峰。自发同步爆发可被氙气抑制。在本研究中，我们通过调节氙气压力来控制神经元培养MEA培养基中的氙气量。我们发现，在分压高于0.3MPa时施加氙气，同步爆发会在几分钟内完全停止。在减压并用新鲜空气吹扫后，同步爆发恢复到原来的频率。因此，我们证实氙气可作为MEA上培养的神经元网络的网络活动抑制剂。但在0.3MPa以下，同步爆发仅受到部分抑制，这取决于氙气的分压。基于分压对神经元网络活动变化的影响，我们发现氙气产生抑制作用的临界浓度约为9.5mM，高于该值时，超过90%的同步爆发活动会被抑制。对氙气 - 空气混合气体进行的进一步系统观察表明，含有少量氙气的压缩空气会抑制同步爆发的抑制作用，这表明存在一种可加速同步爆发的空气成分。
