Dependence of synchronized bursting activity on medium stirring and the perfusion rate in a cultured network of neurons

• Published in: Journal of the Korean Physical Society Vol. 68; no. 9; pp. 1041 - 1048
• Main Authors: Heo, Ryoun, Kim, Hyun, Lee, Kyoung J.
• Format: Journal Article
• Language: English
• Published: Seoul The Korean Physical Society 01.05.2016; 한국물리학회
• Subjects: Mathematical and Computational Physics; Particle and Nuclear Physics; Physics; Physics and Astronomy; Theoretical; 물리학; Synchronized neural burst; Long-term neural recording; Perfusion system for neuronal cell culture; Multi-electrode array; Effect of mechanical stirring on neural activity
• ISSN: 0374-4884; 1976-8524
• DOI: 10.3938/jkps.68.1041

A cultured network of neurons coupled with a multi-electrode-array (MEA) recording system has been a useful platform for investigating various issues in neuroscience and engineering. The neural activity supported by the system can be sensitive to environmental fluctuations, for example, in the medium’s nutrient composition, ph, and temperature, and to mechanical disturbances, yet this issue has not been the subject. Especially, a normal practice in maintaining neuronal cell cultures involves an intermittent sequence of medium exchanges, typically at a time interval of a few days, and one such sudden medium exchange is unavoidably accompanied by many unintended disturbances. Here, based on a quantitative time-series analysis of synchronized bursting events, we explicitly demonstrate that such a medium exchange can, indeed, bring a huge change in the existing neural activity. Subsequently, we develop a medium perfusion-stirring system and an ideal protocol that can be used in conjunction with a MEA recording system, providing long-term stability. Specifically, we systematically evaluate the effects of medium stirring and perfusion rates. Unexpectedly, even some vigorous mechanical agitations do not have any impacts on neural activity. On the other hand, too much replenishment ( e.g. , 1.8 ml/day for a 1.8-ml dish) of neurobasal medium results in an excitotoxicity.