Herman Eugene H, Knapton Alan, Liu Yongmin, Lipshultz Steven E, Estis Joel, Todd John, Woodward Ruth A, Cochran Thomas, Zhang Jun, Poirier Miriam C
Food and Drug Administration, Division of Drug Safety Research, Silver Spring, Maryland, USA
Food and Drug Administration, Division of Drug Safety Research, Silver Spring, Maryland, USA.
Toxicol Pathol. 2014 Jul;42(5):888-96. doi: 10.1177/0192623313505154. Epub 2013 Oct 15.
Cardiac troponins serve as serum biomarkers of myocardial injury. The current study examined the influence of age on serum concentrations of cardiac troponin I (cTnI). An ultrasensitive immunoassay was used to monitor cTnI concentrations in Sprague-Dawley (SD) rats and Erythrocebus patas monkeys of different ages. The mean cTnI concentrations were highest in 10-day-old rats compared to 25-, 40-, and 80-day-old SD rats. Cardiomyocyte remodeling was apparent in hearts from 10-day-old SD rats as evident by hypercellularity, irregularly shaped nuclei, and moderate numbers of myocytes undergoing mitosis and apoptosis. The mean concentration of cTnI in 5 newborn monkeys was considerably higher than that of three 1-year-old monkeys. Evidence of cardiomyocyte remodeling was also observed in these newborn hearts (loss of myofibrils and cytoplasmic vacuolation). Commercial animal serum samples were also analyzed. The concentrations of cTnI detected in fetal equine and porcine serum were considerably higher than that found in adult equine and porcine serum samples Likewise, fetal bovine serum had higher cTnI concentrations (>2,400 pg/ml) than did adult caprine and laprine samples (2.5-2.7 pg/ml). The present study found age-related differences in cTnI concentrations, with higher levels occurring at younger ages. This effect was consistent across several animal species.
心肌肌钙蛋白作为心肌损伤的血清生物标志物。本研究检测了年龄对心肌肌钙蛋白I（cTnI）血清浓度的影响。采用超敏免疫分析法监测不同年龄的Sprague-Dawley（SD）大鼠和赤猴心肌肌钙蛋白I的浓度。与25日龄、40日龄和80日龄的SD大鼠相比，10日龄大鼠的心肌肌钙蛋白I平均浓度最高。10日龄SD大鼠心脏中可见心肌细胞重塑，表现为细胞增多、核形状不规则以及有中等数量的心肌细胞正在进行有丝分裂和凋亡。5只新生猴的心肌肌钙蛋白I平均浓度明显高于3只1岁猴。在这些新生心脏中也观察到心肌细胞重塑的证据（肌原纤维丧失和细胞质空泡化）。还对商业动物血清样本进行了分析。在胎马和胎猪血清中检测到的心肌肌钙蛋白I浓度明显高于成年马和成年猪血清样本中的浓度。同样，胎牛血清中的心肌肌钙蛋白I浓度（>2400 pg/ml）高于成年山羊和成年绵羊样本中的浓度（2.5 - 2.7 pg/ml）。本研究发现心肌肌钙蛋白I浓度存在与年龄相关的差异，年龄越小浓度越高。这种效应在几种动物物种中是一致的。
