Mechanically stimulated non-degenerate AF cells pre-treated with RAD peptides demonstrated increased FAK phosphorylation (tyr397) at the 20 minute timepoint to a similar level as that observed with the CTS only treated cells (77% increase+/−24%), with no significant difference between CTS only, or CTS plus RAD peptide pre-treatment groups (Figure 4). Here, PTK2 is linked to atrial fibrillation.