A Perfusion System for Autonomous Energy Control of the Living Neuronal Circuit.

摘要

Glucose is main source of energy for neurons, and its extracellular concentration is a critical parameter directly linked to life or death. Assuming that the higher probability of the survival of the cell corresponds to 'pleasant' state, it is plausible that a self-inclusive 'value' emerges in a living cell. In addition, it can be constructed a rewarding system, based on the optimization of the extracellular glucose concentration in the cultured neural network. Previous studies suggested that the frequency of spontaneous neuronal electrical activity changed, depending on the extracellular glucose concentration. Thus, the manipulation of the extracellular concentration of glucose should result in the control of the activity of the living neuronal activity. In this study, a perfusion system for mild exchanging of the extracellular solution with different glucose concentration was developed. The spontaneous activity was suppressed during perfusion, even though at the lowest perfusion rate, and we confirmed that the suppression of the activity was caused by extracellular release of adenosine triphosphate (ATP). Apyrase, an extracellular ATP degrading enzyme drastically reduced suppression effect during perfusion and contributes stable spontaneous activity during perfusion. The perfusion system with addition of apyrase can be used for control of the neuronal electrical activity depending on the manipulation of the extracellular energy, which should be originally resulted by the environmental state in the real world.