Localized chemical stimulation of cellular micropatterns using a porous membrane-based culture substrate

We have investigated a technique for the local delivery of chemicals to part of a cellular network. The device for the local stimulation was prepared by binding a permeable substrate made of a porous polycarbonate membrane and a micromask made of an elastomeric poly-(dimethylsiloxane) (PDMS) film having a patterned hole (diameter, 50–200 μm). As the model of the cellular network, primary cardiac myocytes were cultured on the membrane as a monolayer sheet and a line pattern, and then octanol (a gap junctional inhibitor) was locally delivered to the cells from the opposite phase of the porous substrate through a hole in the micromask. Intercellular communications of these cells were evaluated by observing the cytosolic Ca2+ transients. The synchronous Ca2+ transition on a myocyte sheet was stopped at only the area defined by the micromask. Based on the experiments using the line-patterned myocytes, it was proved that the electrically conjugating cellular network was divided into independent parts by the octanol stimulation across the cellular network. This research was carried out with the objective of developing a biosensing system based on a cellular network.