Cardiac contractile proteins in hypertrophied and failing guinea pig heart

Abstract

These observations raise important questions as to the distribution of myosin isoforms in the normal adult guinea pig, and the possibility that myosin ATPase activity might be altered by post-translational modification. Although cardiac myosin ATPase activity correlates with left ventricular performance, it cannot fully explain the depressed performance of failing hearts in this model. Additional immunological studies of cardiac contractile proteins are required as well as studies designed to explore the implications of altered myosin ATPase activity for both contractile function and overall cellular homeostasis.