The sarcomere is the basic unit of myocardial contraction. Each sarcomere is composed of two longitudinal muscle groups: thick filaments and thin filaments. The thick filaments, which are located in the middle of the sarcomeres, 1.5-1.6 mm in length and 10 nm in diameter, are composed of myosin molecules. Myosin (with a molecular weight of 500000 kDa) is a complex, asymmetrical molecule, with a...

BACKGROUND Cardiac troponin is the biochemical gold standard to diagnose acute myocardial infarction. Interestingly however, elevated cardiac troponin concentrations are also frequently observed during and after endurance-type exercise. Oxidative stress associated with prolonged exercise has been proposed to contribute to cardiac troponin release. Therefore, the aim of this study was to assess ...

To diagnose a myocardial infarction, an increase and/or fall in troponin values by at least one value > the 99th percentile in a healthy reference population is required, combined with other ischaemic signs or symptoms (1). Troponin T and troponin I are considered equal in diagnostics of myocardial infarction. There is only one manufacturer of tests for troponin T and thus only one reference ra...

OBJECTIVES This study was done to determine the effects of angiotensin-converting enzyme (ACE) inhibition and other clinical factors on troponin release in non-ST-elevation acute coronary syndrome (ACS). BACKGROUND Troponin is now widely used as a marker of risk in ACS, but determinants of its release have not been defined. METHODS This was a prospective cohort study of 301 consecutive pati...

BACKGROUND The purpose of this study was to derive indices of reperfusion and non-reperfusion after acute myocardial infarction (AMI) from changes in serum concentrations of cardiac troponin T and to test the predictive value of these indices. METHODS The indices were derived from a retrospective analysis of changes in serum troponin T concentration in 71 patients given thrombolytic treatment...

INTRODUCTION AND OBJECTIVES High-sensitivity troponin assays have improved the diagnosis of acute coronary syndrome in patients presenting with chest pain and normal troponin levels as measured by conventional assays. Our aim was to investigate whether N-terminal pro-brain natriuretic peptide provides additional information to troponin determination in these patients. METHODS A total of 398 p...

This review discusses the structure and properties of the isolated components of troponin, their interaction, and the mechanisms of regulation of contractile activity of skeletal and cardiac muscle. Data on the structure of troponin C in crystals and in solution are presented. The Ca2+-induced conformational changes of troponin C structure are described. The structure of troponin I is analyzed ...

We have previously reported the existence of at least four troponin T isoforms in rabbit ventricular muscle and described the changes in their distribution with development. In this report we test whether the proportions of the troponin T isoforms are related to the sensitivity of the myofilaments to calcium. We measured the force-pCa relations in 12 detergent-skinned ventricular strands of car...

OBJECTIVE To assess the relation between troponin concentration, assay precision, and clinical outcomes in patients with suspected acute coronary syndrome. DESIGN Cohort study. SETTING Tertiary centre in Scotland. PARTICIPANTS 2092 consecutive patients admitted with suspected acute coronary syndrome were stratified with a sensitive troponin I assay into three groups (<0.012, 0.012-0.049, ...

Rabbit skeletal-muscle troponin T was phosphorylated by a standard preparation of phosphorylase kinase [Cohen (1973) Eur. J. Biochem. 34, 1--14] and by fractions obtained after chromatography of phosphorylase kinase on phosphocellulose. The original preparation of phosphorylase kinase phosphorylated at least two sites, one of which was serine-1. The second and probably the third sites were pres...