Résumé
The objective of this lecture is to present the helpfulness in using mechanical systems with pre-existing initial stresses to develop modelling devoted to the study of the mechanical behaviour of the cytoskeleton (CSK) and of its structuration during cell spreading. Indeed, it is now well assumed that cell mechanics closely depends on its CSK architecture and on the tension and compression forces carried by its filaments. Among the several models developed up today, those based on the tensegrity analogy or on the divided medium theory have already shown their pertinence. In particular, they appear to be the sole able to consider at the same time: (i) the 3D-structure of the cytoskeleton, (ii) the specific cell anchorage to the substratum via adhesion points (e.g., integrin molecular complexes), (iii) the force balance between tension and compression within the CSK filaments and the role of its resulting internal tension and (iv) the non linear viscoelastic behaviour observed on living adherent cells. The main criticism made about such modelling concerns the difference between the simple architecture usually used regardless the complexity of the CSK structure. This lecture will show two approaches actually developed to lead to more realistic structural models of the cytoskeleton.