Messner B, Baum H, Fischer P, Quasthoff S, Neumeier D
Institut für Klinische Chemie und Pathobiochemie, Klinikum rechts der Isar, Technische Universität München, Germany.
Am J Clin Pathol. 2000 Oct;114(4):544-9.
In the absence of clinical signs, elevated values of the cardiac isoforms of troponin T (cTnT) and I (cTnI) can be found in the serum samples of some patients with skeletal muscle myopathies; the cause is unclear. We studied the messenger RNA (mRNA) expression of cTnT and cTnI in the skeletal muscles of 24 patients with histologically proven myopathies and in 18 patients in whom a myopathy could be excluded. For cTnT- and cTnI-mRNA determination, we designed specific primer pairs for nested polymerase chain reaction. After amplification, the products were digested with 2 restriction enzymes and visualized. We found cTnT mRNA in 7 skeletal muscle biopsy specimens (6 patients with Duchenne muscular dystrophy, 1 patient with a primary sarcoglycanopathy) and cTnI mRNA in 6 (5 with Duchenne muscular dystrophy, 1 patient with a histologically negative biopsy). The mRNA of the cardiac isoforms, cTnT and cTnI, is expressed in the skeletal muscles of patients with Duchenne muscular dystrophy, but also in some other myopathies. Further studies are needed to show whether the mRNA is translated into the protein, but serum levels of cTnT and cTnI in patients with Duchenne muscular dystrophy would seem to indicate this.
在没有临床症状的情况下，一些骨骼肌病患者的血清样本中可发现肌钙蛋白T（cTnT）和肌钙蛋白I（cTnI）的心脏同工型值升高；原因尚不清楚。我们研究了24例经组织学证实患有肌病的患者以及18例可排除肌病的患者骨骼肌中cTnT和cTnI的信使核糖核酸（mRNA）表达。为了测定cTnT和cTnI的mRNA，我们设计了用于巢式聚合酶链反应的特异性引物对。扩增后，产物用2种限制性内切酶消化并进行可视化分析。我们在7份骨骼肌活检标本中发现了cTnT mRNA（6例杜氏肌营养不良症患者，1例原发性肌聚糖病患者），在6份标本中发现了cTnI mRNA（5例杜氏肌营养不良症患者，1例活检组织学检查阴性的患者）。心脏同工型cTnT和cTnI的mRNA在杜氏肌营养不良症患者的骨骼肌中表达，但在其他一些肌病中也有表达。需要进一步研究以表明该mRNA是否会翻译成蛋白质，但杜氏肌营养不良症患者的cTnT和cTnI血清水平似乎表明会发生这种情况。
