Previous studies have demonstrated that expression of p193 and p53 mutants with dominant-interfering activities renders embryonic stem cell-derived cardiomyocytes responsive to the growth promoting activities of the E1A viral oncoproteins. In this study, the effects of p53 and p193 antagonization on cardiomyocyte cell cycle activity in normal and infarcted hearts were examined. Transgenic mice ...

Angiotensin II (Ang II) type 1 (AT1) receptor is known to mediate a variety of physiological actions of Ang II including autophagy. However, the role of AT1 receptor in cardiomyocyte autophagy triggered by mechanical stress still remains elusive. The aim of this study was therefore to examine whether and how AT1 receptor participates in cardiomyocyte autophagy induced by mechanical stresses. A ...

background: the capability of embryonic carcinoma cells p19 in differentiation to cardiomyocyte was examined through inducing effects of oxytocin (ot) and 5-azacytidin (5az) individually and compared with each other in laboratory condition. materials and methods: p19 embryoid bodies (ebs) was formed through hanging drops method. then, ebs were treated with (5az) or (ot) and the eb medium (ctrl)...

RATIONALE Although mitochondrial diseases often cause abnormal myocardial development, the mechanisms by which mitochondria influence heart growth and function are poorly understood. OBJECTIVE To investigate these disease mechanisms, we studied a genetic model of mitochondrial dysfunction caused by inactivation of Tfam (transcription factor A, mitochondrial), a nuclear-encoded gene that is es...

BACKGROUND Physical fitness and level of regular exercise are closely related to cardiovascular health. A regimen of regular intensity-controlled treadmill exercise was implemented and withdrawn to identify cellular mechanisms associated with exercise capacity and maximal oxygen uptake (VO2max). METHODS AND RESULTS Time-dependent associations between cardiomyocyte dimensions, contractile capa...

BACKGROUND Myocyte apoptosis plays an important role in pathological cardiac remodeling and the progression of heart failure. cAMP signaling is crucial in the regulation of myocyte apoptosis and cardiac remodeling. Multiple cAMP-hydrolyzing phosphodiesterases (PDEs), such as PDE3 and PDE4, coexist in cardiomyocytes and elicit differential temporal/spatial regulation of cAMP signaling. However, ...

Young ME. Anticipating anticipation: pursuing identification of cardiomyocyte circadian clock function. J Appl Physiol 107: 1339–1347, 2009. First published July 16, 2009; doi:10.1152/japplphysiol.00473.2009.—Diurnal rhythms in myocardial physiology (e.g., metabolism, contractile function) and pathophyiology (e.g., sudden cardiac death) are well establish and have classically been ascribed to t...

PURPOSE To test the hypothesis that cardiac morphologic differences between Ames dwarf and wild-type littermates might correlate with the increased longevity observed in the Ames dwarf mice. METHODS Hearts removed from young adult (5-7 mo) and old (24-28 mo) Ames dwarf and wild-type littermates underwent histological and morphometric analysis. Measurements of cell size, nuclear size, and coll...

We examined cardiomyocyte intracellular calcium ([Ca2+]i) dynamics and sarcomere shortening dynamics in genetic rat models of left ventricular (LV) hypertrophy associated with or without hypertension (HT) and with or without hyperactive (HA) behavior. Previous selective breeding of the spontaneously hypertensive rat (SHR) strain, which is HA and HT, with the Wistar-Kyoto (WKY) rat strain, which...