TTN and Myocardial fibrosis: In Ba rats, increased collagen deposition, the over-expression of the main enzyme responsible for collagen cross-linking (i.e. LOX), and the hyperphosphorylation of Titin S26-PEVK segment contributed to increased LV myocardial stiffness by augmenting myocardial fibrosis, collagen cross-linking and cardiomyocyte passive tension, respectively.