Human atrial myosin light chain 1 expression attenuates heart failure.

Most patients with hypertrophic cardiomyopathy and congenital heart diseases express the atrial essential myosin light chains (ALC-1) in their ventricles, replacing the ventricular essential light chains (VLC-1). VLC-1/ALC-1 isoform shift is correlated with increases in cardiac contractile parameters of a transgenic rat model overexpressing hALC-1 in the heart (TGR/hALC-1) compared to normal WKY rats. To investigate, whether the benefical effects of the hALC-1 on cardiac contractility could attenuate contractile failure of the overloaded heart, aortocaval shunt operations of 9-10 weeks old WKY and TGR/hALC-1 were performed.

The mitochondrial biogenesis regulatory program in cardiac adaptation to ischemia--a putative target for therapeutic intervention.

The resurgence of mitochondrial biology research stems from the realization that the distinct regulation of mitochondria to meet diverse homeostatic demands is driven by exquisite biochemical and molecular control mechanisms. This program termed mitochondrial biogenesis is integral to orchestrating mitochondrial function and appears to exhibit adaptive remodeling following biomechanical and oxidative stress. The major bioenergetic function of mitochondria partitions the final utilization of oxygen between oxidative phosphorylation and reactive oxygen species.

Regulation of caspase 3 and Fas in pressure overload-induced left ventricular dysfunction.

Background: The presence of apoptotic cell death in cardiac myocytes is now well established and the contribution of apoptosis for the development of heart failure has been suggested. However, the mechanism responsible for the induction of apoptosis remains unclear. The present study was designed to investigate the involvement of Fas and caspase 3 in the transition from pressure overload-induced left ventricular hypertrophy (LVH) to left ventricular dysfunction (LVD).

Rat corin gene: molecular cloning and reduced expression in experimental heart failure.

Stored cardiac pro-atrial natriuretic peptide (pro-ANP) is converted to ANP and released upon stretch from the atria into the circulation. Corin is a serin protease with pro-ANP-converting properties and may be the rate-limiting enzyme in ANP release. This study was aimed to clone and sequence corin in the rat and to analyze corin mRNA expression in heart failure when ANP release upon stretch is blunted.

The carboxyl-terminal ahnak domain induces actin bundling and stabilizes muscle contraction.

Ahnak, a 700 kDa protein, is expressed in a variety of cells and has been implicated in different cell-type-specific functions. In the human heart, we observed an endogenous carboxyl-terminal 72 kDa ahnak fragment that copurified with myofibrillar proteins. Immunocytochemistry combined with confocal microscopy localized this fragment to the intercalated discs and close to the Z-line of cardiomyocytes.