Active response of skeletal muscle: n Vivo experimental results and model formulation

A. Ramírez (1, 2) , J. Grasa (1, 2) , A. Alonso (1, 2) , F. Soteras (3) , R. Osta (3) , M.J. Muñoz (3) , B. Calvo (1, 2)

1 Group of Structural Mechanics and Materials Modelling. Aragón Institute of Engineering Research.University of Zaragoza
2 CIBER-BBN. Centro de Investigación Biomédica en Red en Bioingeniería
3 Lagenbio-Ingen. Aragón Institute of Engineering Research. University of Zaragoza

The contractile properties of the Tibial Anterior (TA) of Wistar rats were measured by means of a multipurpose testing machine. The muscle was isolated from the connective tissues, preserving the proximal insertion. The distal tendon was transected and fixed to the machine actuator. The leg was inmobilized using a pin drilled through the femoral condyle. In this way the force response was studied at different constant lengths for some voltages and frequencies. Mathematical functions are proposed for adjusting the force-length, force-frequency and force-time relations. The model includes a novel formulation for the depression response during muscle tetanization.

Mots clés: Active muscle test; Force-length relationship; Force-frequency relationship; Sag phenomena; Muscle mathematical model

A. Ramírez, J. Grasa, A. Alonso, F. Soteras, R. Osta, et al.. Active response of skeletal muscle: n Vivo experimental results and model formulation. Journal of Theoretical Biology, 2010, 267 (4), pp.546. ⟨10.1016/j.jtbi.2010.09.018⟩. ⟨hal-00637811⟩