近年來由於組織工程與神經科學的進展，神經再生的研究已不再限於理論的階段而進入了實際臨床的應用。其中的關鍵在於如何引導神經元往正確方向再生，且期待此再生程序能夠快速完成。雖已發展出輔助的神經導管以及許多促進再生的藥物，但是針對神經元的機械特性，以及外在物理性刺激對神經再生影響的研究仍在多方發展中。

　　本研究著眼於細胞力學的領域，建立一套能準確量測到細胞力學特性的實驗方法與裝置，能夠精確量測細胞的機械特性，進而評估細胞受到外界刺激後所造成的機械特性變化。本研究的對象暫為纖維母細胞，由於此種細胞近年來廣泛研究，因此用以印證本研究所建立的方法與裝置。首先，在不同的基材包括塑膠、矽膠與PDMS上培養細胞，再以塑膠培養皿所培養的細胞機械特性為標準，與PDMS以及矽膠膜所培養的細胞相比較。實驗的結果發現細胞的楊氏係數會隨著基材種類而改變，PDMS上的細胞最硬，矽膠膜次之，培養皿最軟。其次比較三種不同基材上細胞貼附力量的高低，量測結果發現最大值不超過200nN，培養皿上貼附力量最大，矽膠膜次之，PDMS膜最弱。最後對細胞施與單軸的壓縮作用，藉以評估細胞受外力作用之後的變化。比較細胞與壓縮方向的平行截面與垂直截面上各點的機械性質，發現在細胞周邊區域會產生變化，垂直截面的楊氏係數下降，平行截面的楊氏係數上升。

　　實驗結果與細胞生物學理論一致，所量測的細胞各區域楊氏係數雖略大於文獻中的記載，但亦證明此方法有效且可信，後續研究後將提供神經細胞機械性質量測一個有效的方法。

　　In recent years, the fast progress of tissue engineering and neuro-sciences enhances the research of nerve regeneration. In the research of nerve regeneration process, morphological change and biochemical reaction had been investigated widely, but the mechanical properties and effects of physical stimulations to growth of neural cells remains unclear. To achieve this goal, an effective experimental technique should be developed to measure the mechanical properties of living cells.

　　In this work, the NIH 3T3 fibroblast was utilized for developing the technique, because mechanical properties of this cell are well known. The technique developed will be applied for neurons in next stage of development. An atomic force microscope system with two control modes was employed to measure the topography and the elastograph of the cell. The Young’s modulus was calculated by using the Hertz model.

　　Based on the elastograph the domain of the cell could be separated into three regions, namely, nucleus, cell body and edge. Two experiments are designed to measure the adhesion of 3T3 cells on different substrates and the change of elasticity when the cell is subjected to 10% compression strain.

　　The results showed that the Young’s modulus of cell depends on both the mechanical properties and hydrophilism of substrate. Cells are most stiff when cultured on PDMS film, then silicone rubber film and plastic dish. Cells have largest peak adhesion force when cultured on plastic dish, then silicone rubber film and PDMS film. Young’s modulus distribution of compressed cells is directional dependant, i.e., decreasing in transverse section while increasing in the longitudinal section when compared with uncompressed cells.
　　
　　The trend of our results is in good agreement with the theory of cell biology, although values of the Young’s moduli are higher then those of other studies. An effective and reliable method for measuring the elastograph of living cells has been developed which may be applied for further studies on neural cells.

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