It has long been held as scientific fact that soon after birth, cardiomyocytes cease dividing, thus explaining the limited restoration of cardiac function after a heart attack. Recent demonstrations of cardiac myocyte differentiation observed in vitro or after in vivo transplantation of adult stem cells from blood, fat, skeletal muscle, or heart have challenged this view. Analysis of these stud...

1. Cardiac muscle is a striated muscle, with a sarcomere structure much like that of skeletal muscle. It has small cells (as in smooth muscle), firmly connected end-to-end at the intercalated disks. 2. The action potential in cardiac muscle is long lasting compared to the duration of the contraction, preventing a tetanic contraction. 3. Under normal circumstances, cardiac muscle operates at len...

Several studies have demonstrated the existence of pluripotent bone marrow-derived stem cells capable of homing to injured cardiac and skeletal muscle; however, there has been little evidence demonstrating the induction of tissue-specific endogenous genes in donor stem cells following engraftment. A new study in this issue reports an intriguing finding that raises additional concerns relating t...

The presence of chloride-formate anion exchange in vascular smooth muscle cells (VSMCs) and cardiac myocytes was investigated. Imposing an outward chloride gradient in sarcolemmal microsomes isolated from canine aorta stimulated [W4C]formate uptake compared with the absence of a chloride gradient (24.3±2.33 versus 9.8±1.41 pmol/mg protein for 30 seconds, P<.03) and induced transient uphill ['4C...

SASAKI, R., MORISRLTA, T. and YAMAGATA, S. Estimation of the Cell Number of Heart Muscle in Experimental Cardiac Hypertrophy. Tohoku J. exp. Med., 101 (2), 147-152 •\ The total numbers of heart muscle cells and of interstitial cells were estimated in the Goldblatt rats by a histometrical method. The thickness of muscle fibers and the length of muscle cells were also estimated. The heart weight ...

Caldesmon has been detected in smooth muscle and in a number of non-muscle cells. It binds both actin and myosin and may act as a regulator of contraction or a structural element in smooth muscle. The presence of caldesmon in striated muscle has not been well established. To address this issue, polyclonal antibodies and a panel of monoclonal antibodies were raised against chicken gizzard smooth...

The quest for a test that is absolutely disease-and tissue-specific could be considered the Holy Grail of the clinical chemist, dreamt of but seldom achieved. Initial reports on measurement of the cardiac troponins, cardiac troponin T (cTnT) and cardiac troponin I (cTnI), for diagnosis of myocardial infarction suggested that these markers would become the " gold standard, " replacing all other ...

This paper deals with the mathematical model that describes function of human heart. More specifically, it addresses equations express electromechanical process, is mechanical deformation (contraction and relaxation) heart muscle induced by electrical field that, at every heartbeat, generated in sino-atrial node then propagates all across cardiac cells. After deriving from basic physical princi...