Effects of longitudinal stress after immobilization on proteins related to mechanotransduction of the soleus muscle in weanling rats

Abstract

Physiological or pathological adaptations of the skeletal muscle, as limb immobilization and rehabilitation by exercise, contributes to the cellular perception of mechanical signs, and thus induce changes in muscle function. These ones can become irreversible if not treated, especially when the subject is under development. This study aims to assess the soleus morphological alterations and functional aspects of gait of the weanling rats having the right hind leg immobilized in plantar flexion during 10 days and later submitted to excentric training or manual stretching during 3, 7 and 10 days or then they will be just kept on the cage. The soleus muscle of the immobilized limb will be dissected and frozen for immunohistochemical and immunofluorensce reactions and identification of the costamere proteins (±-actinin, desmin e dystrophin) and type I, III and IV collagens and western blot to these same collagens. Qualitive and quantitative results will be obtained with a Light Microscope and a Leica system of image analysis (LAS V3.7). The gait analyses will be developed before and after immobilization and during the period of training or free period in the cage. Inter- and intra-group data will be treated by statistical techniques like: statistical calculations of the central position (mean, median, mode) and of dispersion (standard and quartile deviations), Student t test for hypothesis, the Wilcoxon-Mann -Whitney test, F (ANOVA and the Kruskal-Wallis test besides graphical methods of description and comparison. (AU)