Protein levels of MsrB1 (SelR), but not MsrB2 or MsrA, are increased in hearts during myocardial hypertrophy. (A) After 7 d of T3- or ISO-treatment, protein extracted from heart tissue was analyzed for MsrB activity. Enzymatic activity was normalized to total protein as determined by Bradford assay. (B) Levels of MsrB1, MsrB2, and MsrA were analyzed by western blot. For each lane, 30 µg total protein was loaded and equivalent loading was verified using anti-α-tubulin. (C) Densitometry was used to estimate quantities of MsrB1 protein detected by western blot. For (A) and (C) results represent mean ± SE (N = 3 per group) with means compared using a student's t test, *p < 0.05.