Abstract
Development and function of neural cells are known to be highly sensitive to structural geometry of scaffold; however, the cellular kinetics depending on the structural geometry is not fully elucidated. Recently, we have established the technique for fabricating microstructurally patterned polystyrene thin films that can be used for microscopic observation even with objectives of high power. Using the patterned films as scaffold, we quantitatively evaluated the effects of microstructural patterns on the morphology and cellular function of NGF-treated PC12 cells, and clarified the mechanisms. GFP imaging revealed that neurite growth of PC12 was strongly influenced by microstructural patterns: the neurite number per cell decreased while the length of a neurite increased. In addition, cell function evaluated using Ca2+ sensitive dye (Fluo4) was greatly affected by microstructural patterns: cellular excitability induced by concurrent electrical filed stimulation was enhanced when compared with the cells on a non-patterned film. However, with regards to cellular excitability to a single cell soma stimulation, no significant effect due to the microstructures was observed. These results indicate that the microstructures are actually behaving as a barrier that causes confined neurite extension, and the enhanced cellular excitability seems to be caused by the modification of electrical environment due to the existence of microstructure rather than the modification of electrical properties of a single cell level. [J Physiol Sci. 2007;57 Suppl:S155]
