骨組織為提供骨骼機械性質與新陳代謝功能的礦化組織，在骨組織中含有三種細胞：造骨細胞、骨細胞與蝕骨細胞。過去有許多研究證實骨組織在受到機械刺激時，細胞會因應機械刺激而改變細胞骨架的組成調節其型態與排列方向適應刺激。
本研究主要目的在於探討造骨細胞的型態變化與機械刺激間的關係。實驗中選用 MG-63 人的造骨細胞，培養在塗布纖維網蛋白的彈性薄膜 24 小時候，分別施加單軸向 5％，1 赫茲、0.5 赫茲、0.17 赫茲與 10％，1 赫茲、0.5 赫茲、0.17 赫茲的刺激，實驗時間為 120 分鐘，每 30分鐘觀察一次，並量化細胞的面積、長度、寬度與排列角度。
實驗結果顯示，細胞受到刺激時，面積與寬度都會隨著實驗的進行而減少，並且其減少的速度會受到拉伸應變的影響；細胞排列也隨著實驗的進行而趨近垂直於拉伸軸向，並且拉伸應變愈大其排列角度愈大。另外對細胞施加雙軸向的拉伸，並在兩個軸向施加不同的拉伸應變刺激 30分鐘。結果顯示：細胞會垂直於應變量較大的軸向排列。

Bone tissue is the mineralized tissue which provided multiple mechanical property and metabolic functions to the skeleton. The bone cells include osteoblasts, osteocytes and osteoclasts. When the bone is subject to the mechanical stimulation, the cell may adjust the morphology and reorient to a particular direction.
In this study, the relationship between cyclic stretch and cell morphology was investigated. We cultured osteoblast cell, MG-63 on the isotropic silicon chamber, which pre-coated fibronectin, and applied uni-axial stretch with 10% strain ratio at 1Hz, 0.5Hz, and 0.17Hz as well as 5% at 1Hz, 0.5Hz, and 0.17Hz, for 120 min respectively. The cell morphology was recorded every 30min by a CCD camera and analyzed by image software. The cell spreading area, length, width, and alignment angle were measured and analyzed.
The results showed that the cell spreading area and width decreased with time, and the decreased rate was influenced by strain ratio. The cell orientation was perpendicular to the stretching direction. The alignment angle between cell’s major axis and stretch axis increased with increasing strain ratio. In addition, we applied the bi-axial stretch to cell with different strain ratio in two axes for 30min. We found that cell orientation was perpendicular to the direction with maximal substrate deformation.

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