Löfberg M, Tähtelä R, Härkönen M, Somer H
Department of Neurology, Helsinki University Central Hospital, Finland.
Arch Neurol. 1995 Dec;52(12):1210-4. doi: 10.1001/archneur.1995.00540360090020.
Myosin is the major structural protein in muscle. Antibodies to beta-type heavy meromyosin react with cardiac and slow-twitch skeletal muscle. Cardiac TnT and TnI were developed as tissue-specific indicators.
To study myosin heavy-chain fragments as a delayed marker of previous rhabdomyolysis. To examine the cardiac specificity of cardiac troponin T (TnT) and cardiac troponin I (TnI) in patients with severe skeletal muscle damage.
Serum myosin heavy-chain fragments, TnT, and TnI were studied up to 12 days after diagnosis in relationship to the serum creatine kinase level in 20 patients with rhabdomyolysis. The mean peak serum creatine kinase activity was 91,300 U/L. Myosin heavy-chain fragments were measured by an immunoradiometric assay, TnT by a one-step immunoenzymometric assay, and TnI by an immunoenzymometric assay.
Values for serum myosin heavy-chain fragments were greater than the upper limit of normal in all patients. The peak value (70 times the upper normal limit, on average) was usually achieved 4 to 7 days after the diagnosis of rhabdomyolysis, and it was increased up to 12 days. The peak level of TnT was increased in 95% of the patients, and it correlated strongly with the peak activity of serum creatine kinase. The highest TnI value was above the detection limit of myocardial infarction in 30% of the patients. Half of these patients were the only patients with ischemic changes observed on an electrocardiogram performed on admission to the hospital.
The measurement of myosin heavy-chain fragments was useful in the diagnosis of previous rhabdomyolysis up to 12 days. The role of TnT was negligible as an indicator of cardiac muscle damage in patients with severe rhabdomyolysis. Cardiac TnI is a more tissue-specific marker for myocardial damage even with concurrent rhabdomyolysis.
肌球蛋白是肌肉中的主要结构蛋白。抗β型重酶解肌球蛋白抗体可与心肌和慢肌纤维骨骼肌发生反应。心肌肌钙蛋白T（cTnT）和心肌肌钙蛋白I（cTnI）被开发为组织特异性指标。
研究肌球蛋白重链片段作为既往横纹肌溶解症的延迟标志物。检测严重骨骼肌损伤患者中cTnT和cTnI的心肌特异性。
在20例横纹肌溶解症患者诊断后12天内，研究血清肌球蛋白重链片段、cTnT和cTnI与血清肌酸激酶水平的关系。血清肌酸激酶活性的平均峰值为91300 U/L。肌球蛋白重链片段采用免疫放射分析测定，cTnT采用一步免疫酶分析测定，cTnI采用免疫酶分析测定。
所有患者血清肌球蛋白重链片段值均高于正常上限。峰值（平均为正常上限的70倍）通常在横纹肌溶解症诊断后4至7天达到，并持续升高至12天。95%的患者cTnT峰值升高，且与血清肌酸激酶峰值活性密切相关。30%的患者cTnI最高值高于心肌梗死检测限。其中一半患者是入院时心电图上观察到有缺血性改变的唯一患者。
肌球蛋白重链片段的检测在诊断既往12天内的横纹肌溶解症中有用。在严重横纹肌溶解症患者中，cTnT作为心肌损伤指标的作用可忽略不计。即使并发横纹肌溶解症，心肌cTnI仍是心肌损伤更具组织特异性的标志物。
