Acute effects of short duration, maximal exercise on cardiac troponin I in healthy horses

Abstract

This study evaluated the effects of exercise on cardiac troponin I (cTnI) concentrations in healthy, adult horses. Fifteen fit, healthy horses determined to have a normal cardiovascular system completed a standardized exercise test on a high-speed treadmill. Heparinized blood was collected for plasma cTnI concentrations before maximal exercise, and 1, 3, 6, 9, 12 and 24 h post-exercise. The cTnI concentrations were measured with a commercial system (Stratus CS, Dade Behring, Inc.). Results were analysed by a multivariate ANOVA, where indicated post hoc analysis was done by Tukey-Kramer HSD and significance was placed at p , 0.05.All horses had elevations in cTnI concentrations after maximal exercise. Values for cTnI trended higher at 3 h (0.066^0.011 ng ml 21 ) and 6 h (0.062^0.011 ng ml 21 ) post-exercise compared with pre-exercise (0.039^0.007 ng ml 21 ), although this did not reach statistical significance. Mean cTnI concentrations were within our normal reference range at all time points, although four individuals were above our normal range after exercise.These data show that short-term, high-intensity exercise induces a small rise in plasma cTnI in normal horses. This should be kept in mind when evaluating cTnI concentrations in horses that have recently completed intense exercise. In addition, these data suggest that 3-6 h after intense exercise may be the optimal time for measurement of cTnI concentrations in horses with suspected exercise-induced myocardial damage.

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.…”

“…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].…”

Exame Eletrocardiográfico Em Equinos Da Raça Puro Sangue Árabe Submetidos Ao Exercício Em Esteira De Alta Velocidade E À Suplementação Com Vitamina E

“…Entretanto, a disfunção miocárdica causada pelo exercício parece ser de difícil avaliação (Durando et al, 2006). Os mecanismos intercorrentes do exercício físico responsáveis pela lesão miocárdica e disfunção cardíaca resultante ainda precisam ser elucidados.…”

Malondialdeído e troponina I cardíaca em equinos da raça Puro Sangue Árabe submetidos ao exercício e à suplementação com vitamina E

“…No entanto, neste estudo, não foi possível correlacionar as concentrações séricas do indicador de lipoperoxidação, o MDA, com as de cTnI. Muitos trabalhos descrevem que a cTnI do miocárdio equino apresenta alta reação cruzada com os kits de imunoensaios humanos de cTnI, podendo ser utilizada como biomarcador de lesão de cardiomiócitos (YONEZAWA et al, 2010 DURANDO et al (2006), que relataram uma elevação discreta das concentrações de cTnI em 3 a 6h, retornando aos níveis pré-exercício em 24 horas após exercício de alta intensidade e curta duração em esteira, em equinos de corrida de diversas raças.…”

“…Embora existam poucos relatos sobre a concentração de cTnI em equinos saudáveis, esses valores normais são variáveis. Essas diferenças são atribuídas aos diversos sistemas analisadores, que utilizam aminoácidos distintos para composição dos anticorpos monoclonais (DURANDO et al, 2006). Para MICHIMA (2007), a tentativa de extrapolar os resultados com aqueles apresentados na literatura, em equinos, é dificultada, uma vez que há divergência de metodologias e tipos de amostragem.…”