Diagnostic and monitoring values of peripheral blood cardiac troponin Ⅰmessager RNA for myocardial damnification / 中国组织工程研究

ABSTRACT

BACKGROUND: Cardiospecific proteins of the troponin-tropomyosin complex in the contractile system of the cardiomyocytes have challenged creatine kinase isoenzyme MB (CK-MB) as the "gold standard" for the early biochemical detection of acute myocardial injury.OBJECTIVE: To investigate cardiac troponin Ⅰ messager RNA (cTnI-mRNA) in peripheral blood and its clinical values in diagnosis of patients with myocardial injury.DESIGN: A basic and observational study for set up a method to analyze cTnI-mRNA.SETTING: Department of Cardiology, Affiliated Hospital, Nantong University.MATERIALS The project was accomplished from May 2003 to May 2005 in Research Center of Clinical Molecular Biology, and Department of Pathology, Affiliated Hospital, Nantong University. The cTnI-mRNA was detected from blood by a nested PCR assay, and its clinical values as a sensitive myocardial diagnostic marker were confirmed in patients with myocardial injury.METHODS: Pathologic features and microstructure of cardiac myocytes were examined by H&E staining or electron microscopy. The cTnI-mRNA was extracted from blood and synthesized to cDNA through random primers and reverse transcriptase, and amplified by a nested PCR assay, and its clinical values as a myocardial diagnostic marker were investigated in patients with myocardial injury.MAIN OUTCOME MEASURES: Microstructure of cardiomyocytes, sensitivity of analysis method and diagnostic values.RESULTS: Microstructure of cardiomyocytes with mitochondria swell,rupture, vacancy-like denaturation, nucleus abnormality, and chromatin condensed were observed by electron microscopy. The cTnI-mRNA fragments from heart and blood were successfully amplified and the sensitivity was 2 pg/μL. The product sequences from tissues or blood were confirmed by sequencing. The cTnI-mRNA from cardiac myocytes was found that it present in blood plasma and not in circulating nucleus cell. The incidence of blood cTnI-mRNA of chronic cardiomyopathy was significantly higher (P ＜ 0.05) than that of serum enzymatic patterns or cTnI quality,respectively.CONCLUSION: The analysis of blood cTnI-mRNA is a sensitive marker for diagnosis and monitoring of myocardial injury.