Resting concentrations of cardiac troponin I in fit horses and effect of racing

Influence of Cavalcade of Different Distances on the Serum Concentrations of the Cardiac Biomarkers Troponin I (Ctni) and Creatine Kinase Myocardial Band (CK-MB) in Horses

“…with exercise such as fitness status, electrolyte imbalances, and dehydration could not be determined from the results of this study. Increased concentrations of cTnI have also been reported in connection with high-intensity activity, short and moderate-duration exercise, and in endurance horses without signs of cardiac disease [11,12,13,14 ]. The causes of exerciseinduced cTnI concentrations are not clear.…”

“…One theory suggests that the increases in cTnI concentrations may be explained by mild hypoxia during exercise. The hypoxia could cause a change in the permeability of myocardium, resulting in the leakage of macromolecules into blood flow [11,12,13]. found that short periods of hypoxia can induce release of cTnI without cell death in rats Piper, et al [20].…”

“…cTnI is also increase with non-cardiac diseases that induces secondary cardiac involvement, as example with babesiosis and endotoxaemia [9,10]. Release of cTnI during and after exercise also has been described in equine athletes after racing or race training, endurance rides or treadmill exercise [11,12,14,13]. Creatine Kinase-Myocardial Band (CK-MB) is another cardiac biomarker that has been reported to increase with exercise and with chest pain in humans [15].…”

Marcadores cardíacos na medicina veterinária

“…Embora o mecanismo ainda não tenha sido totalmente elucidado, especula-se que o aumento pós-exercício seja devido ao aumento da permeabilidade da membrana celular do miocárdio e à liberação de cTnI livre do citosol e não devido à necrose permanente e morte celular (NOSTELL & HÄGGSTRÖM, 2008). Equinos que realizam teste de exercício máximo tornamse hipoxêmicos e possuem maior estresse cardiovascular, por isso apresentam leve aumento da cTnI (DURANDO et al, 2006).…”

Biochemical abnormalities of athletic horses

“…38 Suggested reference limits for cTnI have been established in athletic Thoroughbred, Standardbred and Warmblood populations, and in horses with monensin-induced cardiac disease, but are potentially assay dependent. 38,[40][41][42][43] Most healthy horses have low plasma cTnI values in the absence of cardiac disease, regardless of whether they are sedentary or involved in regular athletic training. 38,40 Brief intense racing exercise can provoke mild elevations in some individuals that might persist for more than 14 hours.…”