BACKGROUND Evidence indicates that myocardial NO production can modulate contractility, but the source of NO remains uncertain. Here, we investigated the role of a type 1 NO synthase isoform (NOS1), which has been recently localized to the cardiac sarcoplasmic reticulum, in the regulation of basal and beta-adrenergic myocardial contraction. METHODS AND RESULTS Contraction was assessed in left...

T HE phenomenon to which Pollack gives the name "stepwise shortening" (though he claims that similar steps occur also during passive lengthening) is clearly of great interest if it is genuine; indeed, Pollack claims that it requires fundamental rethinking of current ideas about the mechanism of contraction. Before any such conclusion can be reached, however, three questions must be answered: Fi...

Background: Ca is the most important minerals in the body that plays a key rols in the physiological activities, anzymatic reaction and the regulation of myocardial contraction and relax-ation. Ca deficiency causes the heart failure and decrease cardiac contractility. OBJECTIVES: To determine the effects of long-term dietary calcium deficiency on the heart function of layer hens based on the el...

The diagnostic approach of patients with coronary artery disease normally relies on the assessment of global and regional perfusion and contraction in the normal and pathological areas of the myocardium. However, experimental pathophysiological studies have clearly shown that microvascular flow, metabolic consumption and the strength of contraction do not behave homogeneously in the different t...

Myocardial infarction after coronary artery bypass graft (CABG) surgery has been described clinically in up to 30% of patients but there is little morphologic information about the character and pathogenesis of the myocardial injury. We studied myocardium in the distribution of bypassed and nonbypassed coronary arteries for the presence of contraction band necrosis as compared to coagulation ne...

BACKGROUND Long-QT syndrome (LQTS) is characterized by prolonged myocardial action potential duration. The longest action potential duration is reported in the endomyocardium and midmyocardium. Prolonged action potential duration in LQTS may cause prolonged cardiac contraction, which can be assessed by strain echocardiography. We hypothesized that myocardial contraction is most prolonged in sub...

Background—Long-QT syndrome (LQTS) is characterized by prolonged myocardial action potential duration. The longest action potential duration is reported in the endomyocardium and midmyocardium. Prolonged action potential duration in LQTS may cause prolonged cardiac contraction, which can be assessed by strain echocardiography. We hypothesized that myocardial contraction is most prolonged in sub...

background: ca is the most important minerals in the body that plays a key rols in the physiological activities, anzymatic reaction and the regulation of myocardial contraction and relax-ation. ca deficiency causes the heart failure and decrease cardiac contractility. objectives: to determine the effects of long-term dietary calcium deficiency on the heart function of layer hens based on the el...