The value of troponin assays in modern medical practice

Abstract

Cardiac troponins – C, I and T – form part of the troponin complex which is involved in the regulation of the calcium-mediated interaction of actin and myosin in myocytes. Each troponin has a different role in the above mentioned complex. Troponin C is involved in binding calcium, troponin I inhibits interaction of actin to myosin, while Troponin T binds to tropomyosin and facilitates muscle contraction. Both skeletal as well as cardiac muscle types express troponin C, however the amino acid sequences of troponin I and troponin T are unique to cardiac muscle. It is the specificity of these latter troponins to cardiac muscle that allowed for the development of quantitative assays that detect elevations of troponins in the serum once released by damaged cardiac muscle tissue.1