We formulated a mass-spring system model of the apical membrane of the cell to describe the deformation of a vascular endothelial cell under substrate stretching. The motion of each mass was governed by the equation of motion with an artificial damping effect, and the force was derived from the energy which was formulated by Wada and Kobayashi (2003) for a red cell. The energy was the sum of an elastic energy of springs in tension/compression, that of triangular elements in bending, constraints of the cellular volume and surface area. The cellular geometry was constructed from a set of images obtained by confocal scanning laser microscopy. The numerical simulation was performed under the condition of pure uniaxial stretching of a substrate by 10%, and was compared with results from a finite element analysis of a hyperelastic whole cell model. A comparison suggested a necessity of an evaluation of cytoskeletons.
