Changes in α7β1 integrin signaling after eccentric exercise in heat‐shocked rat soleus

ABSTRACT Introduction α7β1 integrin links the extracellular matrix to the focal adhesion (FA) in skeletal muscle and serves as a stabilizing and signal relayer. Heat shock (HS) induces expression of proteins that interact with the FA. Methods Male Wistar rats were assigned to 1 of 3 groups: control (CON); eccentric exercise (EE); or EE+HS (HS). Soleus muscle was analyzed at 2 h and 48 h post‐exercise. Results The 120‐kDa α7 integrin decreased in the EE and HS groups, and the 70‐kDa peptide decreased in the EE group at 2 h post‐exercise. Total expression of focal adhesion kinase (FAK) and RhoA were decreased in EE and HS at 2 h post‐exercise. Expression of phosphorylated FAK 397 decreased in the EE group but not the HS group at 2 h post‐exercise. Conclusions Long‐duration EE may cause alterations in the FA in rat soleus muscle through the α7 integrin subunit and FAK. Muscle Nerve 51: 562–568, 2015