^(131)I-β-CIT多巴胺转运蛋白显像的基础研究  

Basic Study of Dopamine Transporter Imaging with ^(131)I-β-CIT

作　　者：叶斌[1] 匡安仁[1] 丁昊[1] 郑洪波[2] 袁强[2] 何莉[2] 

机构地区：[1]四川大学华西医院核医学科,成都610041 [2]四川大学华西医院神经内科,成都610041

出　　处：《生物医学工程学杂志》2003年第4期653-656,共4页Journal of Biomedical Engineering

摘　　要：用过氧乙酸法进行 1 31 I标记 β- CIT。以 MPTP连续 5 d注入猫股静脉内 ,建立 PD模型。取正常猫 6只、PD模型猫 3只 ,每只分别注入 74 MBq/ 0 .5 ml　 1 31 I- β- CIT,观察 4 h和 2 0 h时动物体内分布情况。将 74 MBq/0 .5 ml/只 1 31 I- β- CIT经股静脉分别注入正常组及 PD组猫体内 ,于注射后 0 .5、1、2、4、2 0 h进行脑显像 ,计算纹状体 1 31 I-β- CIT的特异性结合。结果显示 :标记物 1 31 I-β- CIT放化纯达 97.6 2 %± 0 .31%。室温下放置 4 h以及分别与水、人新鲜血清孵育 4 h后 ,放化纯平均值分别为 95 .33%± 0 .5 9%、95 .14 %± 0 .87%、95 .0 6 %± 0 .6 4 %。猫静脉注射 1 31 I- β- CIT后 ,放射性主要浓聚于纹状体区 ,其次为肺、肝、肾。以每克组织中放射性占总放射性计数的百分比计算 ,正常猫 4 h和 2 0 h纹状体 /小脑比值分别为 18.31± 3.5 0和 2 0 .5 1± 2 .2 3。 2 0 h PD猫纹状体 /小脑的比值为 11.2 0± 0 .2 9,与 2 0 h正常猫相比显著下降 (P<0 .0 5 )。显像研究显示正常猫纹状体 2 0 h特异性结合为 4 .83± 0 .82 ,PD模型猫为 2 .92± 0 .6 6 ,两者有显著性差异 (P<0 .0 5 )。分布研究与显像研究的结果相符。因此 ,β- CIT是一种较理想的 DAT配体 ,碘标 β- CIT的CIT was labled with 131 I by the peracetic acid method. Cat model of Parkinsonism was set up with MPTP. Each of normal and PD model cats was given an injection of 74 MBq/0.5ml 131 I β CIT into the femur vein. Then the blood samples were obtained at 4h and 20h ,the radioactivity was counted with calibrator.The biodistribution data of 131 I β CIT in cat body was calculated(ID%/g).The cats were subjected to imaging at 0 5h,1h,2h,4h,20h after the administration of radiopharmaceutical.The radioactivity in striatum and cerebellum was measured and striatal specific binding ratios were calculated. The Results showed that the radio chemical purity of 131 I β CIT was 97.62%±0.31%. The 131 I β CIT remained stable for at least 4h after incubation with water and serum respectively.Following intravenous administration in cats, 131 I β CIT showed high accumulation in striatum.The study of imaging in cats showed that striatal specific uptake of 131 I β CIT at 20h after injection was 4.83±0.82 in normal cats and 2.92±0.66 in PD cats.There was a significant reduction of striatal tracer uptake in PD cats, compared to the controls.The results of biodistribution study was in agreement with the results of imaging study. These results suggest that β CIT is an ideal agent for dopamine transporter imaging and can be used for the diagnosis of Parkinson's disease.

关 键 词：^131I—β—CIT 多巴胺转运蛋白 显像 帕金森氏病 

分 类 号：R817.4[医药卫生—影像医学与核医学]