(99m)~Tc标记抗心肌肌钙蛋白T单抗Fab片段在SD大鼠急性心肌梗死模型中的生物学分布

Biological Distribution of ^99mTc-AcTnTMA-Fab in the SD Rats with Acute Myocardi-al Infarction

目的研究99mTc标记抗心肌肌钙蛋白T单抗片段(99mTc-AcTnTMA-Fab)在急性心肌梗死大鼠模型中的生物学分布规律。方法先制备99mTc-AcTnTMA-Fab和99mTc-AcTnTMA,并建立急性心肌梗死大鼠模型。本研究分为实验组、对照组和空白组,每组20只大鼠。实验组急性心肌梗死大鼠静脉注射99mTc-AcTnTMA-Fab 0.3 mCi,分别于注射后2 h、4 h、8 h、12 h时处死(每时间点5只),取血液、肝、脾、肾、肌肉、结肠、肺、心脏,以计算每克组织放射性计数占总注射计数的百分比(ID%/g)及梗死心肌ID%/g/肺ID%/g比(HLR)。对照组急性心肌梗死大鼠和空白组正常心肌大鼠分别静脉注射99mTc-AcTnTMA和99mTc-AcTnTMA-Fab 0.3mCi,其它处理方法同实验组。结果实验组和对照组的ID%/g和HLR均较空白组显著为高,提示急性梗死心肌对99mTc-AcTnTMA-Fab和99mTc-AcTnTMA的摄取均是特异的,且实验组的ID%/g和HLR较对照组显著为高,提示99mTc-AcTnTMA-Fab摄取能力更强。结论99mTc-AcTnTMA-Fab有望作为亲心肌梗死显像剂用于诊断急性心肌梗死。

Aim To investigate the biological distribution of 99mTc-AcTnTMA-Fab in the SD rats with acute myocardial infarction. Methods 99mTc-AcTnTMA was prepared and the rat model of acute myocardial infarction was built. Then 60 rats were randomized into experimental group,control group and blank group. There were twenty rats in each group. In the experimental group,20 rats with acute myocardial infarction were injected with 0.3 mCi 99mTc-AcTnTMA-Fab and were killed 2 h,4 h,8 h and 12 h after injection respectively （5 rats）. Blood,liver,spleen,kidney,muscle,colon,lung and heart of each rat were taken and the injected dosage （ID%/g） and the ratio of ID%/g for heart to lung （HLR） was calculated. In the control group,20 rats with acute myocardial infarction were injected with 0.3 mCi 99mTc-AcTnTMA and were killed with subsequent procedure in the same way as the experimental group. In the blank group,20 normal rats were injected with 0.3 mCi 99mTc-AcTnTMA-Fab and were killed with subsequent procedure in the same way as the experimental group. Results The value of ID%/g and HLR in the experimental group and the control group were significant higher than those in the blank group,which hinted that acute myocardial infarction could uptake specifically the 99mTc-AcTnTMA-Fab and 99mTc-AcTnTMA. The value of ID%/g and HLR in the experimental group was significant higher than those in the control group,which hinted that infarction tissue uptake of 99mTc-AcTnTMA-Fab was more than99mTc-AcTnTMA. Conclusions 99mTc-AcTnTMA-Fab could be a useful tracer of myocardial imaging to diagnose acute myocardial infarction.