Effect of off-axis cell orientation on mechanical properties in smooth muscle tissue

P. A. Sarma, Ramana M. Pidaparti, Richard A. Meiss

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DOI: 10.4236/jbise.2011.41002                

Abstract

The cell alignment in a smooth muscle tissue plays a significant role in determining its mechanical proper-ties. The off-axis cell orientation "θ” not only effects the shortening strain but also modifies the shear stress relationship significantly. Both experiments and finite element analysis were carried out on a tracheal smooth muscle strip to study how the cell alignment in smooth muscle affects the shear stiffness and shear stresses as well as deformation. A simple model for shear stiffness is derived using the data from experiments. Shear stiffness results obtained from the model indicate that the muscle shear stiff-ness values increase non-linearly with strain and with higher off-axis alignment of cells. Results of deforma-tion and shear stresses obtained from finite element analsysis indicate that the maximum shear stress values of tracheal smooth muscle tissue at 45% of strain are 2.5 times the corresponding values at 20% of strain for all three off-axis cell orientation values θ = 15?, 30? and 45?.

Keywords

Smooth Muscle; Shear Stress; Finite Element Model; Cell Orientation; Shortening Strain

Conflicts of Interest

The authors declare no conflicts of interest.

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