Abstract 19380: Cardiac Contractile Protein Expression of the Right Ventricle in End Stage Human Heart Failure
Objectives: Little is known about right ventricular (RV) remodeling in human end-stage heart failure (HF). We sought to study RV contractile protein expression in HF.
Methods: Western Blot (WB) analyses were performed on protein samples prepared from the RV and left ventricle (LV) free walls of 10 explanted human hearts (5 ischemic, ISC; 5 non-ischemic, N-ISC) and two normal (NOR) donor hearts. Tissues were homogenized in lysis buffer, subjected to electrophoresis gel separation and immune-blotted with antibodies against Myosin Heavy Chain 7 (MHC), Myosin Light Chain 3 (MLC), Troponin I type 3 (TNI), Tropomyosin 1 alpha (TRP), alpha Actinin-2 (ACT) and Desmin (DSM). GAPDH served as an internal loading control. The fluorescent intensity of reactive bands was detected by Li-Cor and band densities were quantified using Image Studio software.
Results: We previously identified distinct RV and LV proteomic signatures in ISC in HF and confirmed these results by WB (Figure 1). In this study focused on the RV alone, we compared contractile protein expression in NOR, ISC and N-ISC RV (Figure 2). Expression of MHC and TNI was decreased and expression of MLC, TRP and DSM increased in both ISC and N-ISC RV compared to NOR. Expression of ACT was decreased in N-ISC RV but increased in ISC RV compared to NOR.
Conclusions: RV contractile proteins exhibit distinctive expression patterns in human ISC and N-ISC HF compared to normal expression patterns in controls. In HF, RV expression of MLC and TRP is significantly increased and RV expression of MHC is significantly decreased. ACT RV expression is decreased only N-ISC HF.
- © 2012 by American Heart Association, Inc.