(A) Representative Western blots for phosphorylated (Ser2448) and total mTOR, phosphorylated (Thr389) and total S6K, phosphorylated (Ser473) and total Akt, phosphorylated (Thr172) and total AMPK, phosphorylated (Thr202/Tyr204) and total ERK1/2, and GAPDH (loading control) at 8 days of static (S) or dynamic (D) culture or 24 hours after switching from static to dynamic culture (S→D) or from dynamic to static culture (D→S) at culture day 7. (B) Quantified ratio of phosphorylated/total protein for each kinase in (A), normalized to static (S) group (n = 4 samples per group from 2 cell isolations, each sample is lysate of 4 cardiobundles pooled together). *, p < 0.05 vs. static; #, p < 0.05 vs. dynamic.