放射性核素标记心肌肌球蛋白重链单抗检测心肌损伤的实验研究

Erperimental Study of radioimmunoimaging using cardiac myosin heavy chain McAb for the detection of myocardial damage

为探讨急性心肌梗塞病灶心肌细胞损伤程度，采用放射性核素标记心肌肌球蛋白重链（CMHC）单克隆抗体（McAb）进行了实验性心肌损伤大鼠和心梗模型犬的研究。125I－CMHCMcAb注射大鼠后4h，标记抗体即已进入坏死心肌靶组织，8h达最高值。实验组心肌／对照组心肌比值为2．86。99mTC-CMHCMcAb犬显像，实验组中有3只于6h心肌梗塞灶显影清晰，4只于8h显影清晰,阳性检出率为70％。动物实验提示；大鼠损伤心肌对CMHCMcAb的结合力高于正常心肌，心梗模型犬CMHCMcAb放免显像阳性检出率高，可为临床急性心肌损伤检测提供可靠的定位诊断依据。

Radioimmunodetection using 125I and 99mTc-labelled cardiac myosin heavy chain (CMHC) monoclonal antibody (McAb) was undertaken to assess myocardial damage in acute myocardial infarction(AMI) model of rats and dogs. 125I-CMHC McAb was already found in infarcted area at 4h after injection and the highest uptake value was at 8h in rats. The uptake ratio of 125I-CMHC in infarcted area of experimental group to that in normal cardiac area of contral group was 2.86. 99mTc-CMHC McAb was injected intravenously to the dogs with AMI. In SPECT imaging, infarcted area were clearly visualized at 6h post injection. The positive rate was 70%. It is concluded that radiolabelled CMHC McAb can visualize infarcted area by SPECT and the findings suggest that this method is effective for locltization of myocardial damage.