Cummins B, Auckland M L, Cummins P
Am Heart J. 1987 Jun;113(6):1333-44. doi: 10.1016/0002-8703(87)90645-4.
The cardiac isotype of the myofibrillar contractile protein, troponin-I, is located specifically in the mammalian heart. A sensitive radioimmunoassay has been developed to detect human and nonhuman primate cardiac troponin-I in serum down to 10 ng/ml. Immunochemical cross reactivity with skeletal troponin-I was only 2% and was species nonspecific. Normal patient levels of cardiac troponin-I are about 10 ng/ml. In patients with acute myocardial infarction (n = 32), serum cardiac troponin-I was elevated within 4 to 6 hours, reached a mean peak level of 112 ng/ml (range 20 to 550 ng/ml) at 18 hours, and remained above normal for up to 6 to 8 days following infarction. Peak cardiac troponin-I correlated with peak creatine kinase (CK) MB isoenzyme (r = 0.75). In subjects (n = 34) with skeletal muscle damage (total CK = 338 to 5384 IU/L), cardiac troponin-I levels were not elevated above normal, although CK-MB isoenzyme was elevated in some patients. Cardiac troponin-I levels were normal or slightly elevated in patients with ischemic heart disease and were normal in patients with chest pain of noncardiac origin. Immunoassay of cardiac troponin-I could be a valuable diagnostic aid in the cardiac-specific detection of cell necrosis.
肌原纤维收缩蛋白肌钙蛋白I的心脏同种型特异性地存在于哺乳动物心脏中。现已开发出一种灵敏的放射免疫测定法，可检测血清中低至10 ng/ml的人类和非人类灵长类动物心脏肌钙蛋白I。与骨骼肌肌钙蛋白I的免疫化学交叉反应仅为2%，且无物种特异性。正常患者的心脏肌钙蛋白I水平约为10 ng/ml。在急性心肌梗死患者（n = 32）中，血清心脏肌钙蛋白I在4至6小时内升高，在18小时时达到平均峰值水平112 ng/ml（范围为20至550 ng/ml），并在梗死后长达6至8天内保持高于正常水平。心脏肌钙蛋白I峰值与肌酸激酶（CK）MB同工酶峰值相关（r = 0.75）。在骨骼肌损伤患者（n = 34）中（总CK = 338至5384 IU/L），尽管部分患者的CK-MB同工酶升高，但心脏肌钙蛋白I水平未高于正常。缺血性心脏病患者的心脏肌钙蛋白I水平正常或略有升高，非心脏源性胸痛患者的心脏肌钙蛋白I水平正常。心脏肌钙蛋白I的免疫测定在细胞坏死的心脏特异性检测中可能是一种有价值的诊断辅助手段。
