Cardiac troponin may be released by ischemia alone, without necrosis

Date

2010

Authors

Hickman, Peter
Potter, Julia
Aroney, Con
Koerbin, Gus
Southcott, Emma K
Wu, Allan
Roberts, M

Journal Title

Journal ISSN

Volume Title

Publisher

Elsevier

Abstract

Whilst it is formally stated that cardiac troponin is only released when cardiac myocytes undergo necrosis, there are a number of clinical situations where troponin is present in the circulation, without any apparent cardiac injury. In these cases, troponin half-life in the circulation is usually substantially shorter than that seen when troponin is released following myocardial infarction with frank necrosis. A mechanism has been described in liver, where large cytoplasmic molecules can pass from the intra- to extra-cellular space without cellular necrosis occurring. This occurs by the formation of membranous blebs which bud off from the plasma membrane of the cell. Blebs develop during cellular ischemia. If the ischemia is limited and re-oxygenation occurs, the blebs may be released into the circulation without rupture of the plasma membrane, resulting in a one-off release of cytoplasmic contents including macromolecules. Evidence from cardiac studies is presented supporting the presence of membranous blebs in cardiac myocytes, enabling troponin to be released from cardiac cells due to ischemia alone, without necrosis.

Description

Keywords

Keywords: troponin I; acute coronary syndrome; cell damage; cell death; cell ischemia; cell membrane; cellular distribution; circulation; cytoplasm; half life time; heart infarction; heart muscle cell; human; liver; nonhuman; priority journal; protein function; pro Blebs; Integrins; Ischemia; Necrosis; Troponin I; Troponin T

Citation

Source

Clinica Chimica Acta

Type

Journal article

Book Title

Entity type

Access Statement

License Rights

DOI

10.1016/j.cca.2009.12.009

Restricted until

2037-12-31