Microtunnel-Based Recording for Evaluating Axon Conduction Change after Chemical Treatment

Brain is composed of a great number of neurons, which interconnect via axons. Although axons were regarded as digital cable in conventional view, recently that is thought as analogue cable and a computational unit. Here, we developed a microdevice to guide axons on multiple electrodes, and record response of axons to chemical reagent. Microfabrication based structural guidance and surface treatment with cell adherent and repellent reagent were combined to make a novel device. Then, changes in axonal conduction delay with various concentration of sodium channel blockers was recorded to evaluate suitability of our method. Axon showed different concentration dependent changes to tetrodotoxin and lidocaine, suggesting that our device is capable to detect dose-dependent response of axons.