Differential reactivity of cardiac and skeletal muscle from various species in a cardiac troponin I immunoassay.
To identify a blood test that can differentiate cardiac from skeletal muscle injury in animals, we compared tissue reactivities for various species with the use of an immunoassay for human cardiac troponin I (cTnI). Tissue reactivity varied as a function of the homology of tissue troponin with human cTnI. Cardiac reactivity in large mammals was equivalent to cTnI, 9.8 +/- 0.6 mg/g, and was 2-fold, 10-fold, and 100-fold greater than in small mammals, birds, and fish, respectively. Skeletal muscle reactivity was equivalent to cTnI, 5.1 +/- 0.6 micrograms/g, in all species except fish, in which it was 50% lower. The ratio of reactivities of cardiac and skeletal muscle was: 1800 in large mammals, 1100 in small mammals, 230 in birds, and 43 in fish. We conclude that cTnI is a powerful candidate in mammals, a possible candidate in birds, but unlikely to be of use in fish as a sensitive and tissue-selective diagnostic test for cardiac injury.
O'Brien
P J
PJ
Human Safety Department, 500 Miami Valley Laboratories, Procter and Gamble Co., Cincinnati, OH 45253, USA.
Landt
Y
Y
Ladenson
J H
JH
D000818:Animals; D015415:Biomarkers / Q000032:analysis; D009202:Cardiomyopathies / Q000175:diagnosis / Q000378:metabolism; D002417:Cattle; D002645:Chickens; D004285:Dogs; D006736:Horses; D006801:Humans; D007118:Immunoassay; D051379:Mice; D018482:Muscle, Skeletal / Q000378:metabolism*; D009206:Myocardium / Q000378:metabolism*; D017686:Oncorhynchus mykiss; D011817:Rabbits; D051381:Rats; D017207:Rats, Sprague-Dawley; D012756:Sheep; D013045:Species Specificity; D013552:Swine; D014336:Troponin / Q000032:analysis*; D020107:Troponin T; D014421:Turkey
D015415:Biomarkers; D014336:Troponin; D020107:Troponin T