^(99)Tc^m-MAVGG-Glu的肿瘤定位性能

Tumor Locating Property of ^(99)Tc^m-MAVGG-glucose

用99Tcm标记了β-N-巯基乙酰基-缬氨酰-甘氨酰-甘氨酰-葡萄糖(MAVGG-Glu),对标记物在荷S180肉瘤在小鼠体内的生物分布与显像进行了研究,并与18F-FDG的生物分布进行对比。结果显示,99Tcm对MAVGG-Glu的标记率大于90%。注射后3 h和5 h,99Tcm-MAVGG-Glu在肿瘤中的摄取率分别为1.46±0.41和1.28±0.24%ID/g;注射后5 h,肿瘤与除肝、肾外的正常组织的放射性摄取比(T/NT)均高于1.8,其中肿瘤与血液、肿瘤与肌肉和肿瘤与脑的T/NT分别为4.41、4.00和8.53。静脉注射3 h后,肿瘤即可显影,随时间延长,肿瘤与正常组织的对比度略有增高。以上结果提示,99Tcm-MAVGG-Glu有可能应用于肿瘤显像。与18F-FDG相比,99Tcm-MAVGG-Glu在肿瘤中的摄取率以及肿瘤与大多数组织的T/NT均较低,但肿瘤与肌肉、心脏、脾和脑的T/NT高于18F-FDG,尤其是肿瘤与脑的T/NT显著高于18F-FDG,提示其在脑瘤以及大脑附近的肿瘤显像中较18F-FDG更具优势。

To develop 99Tcm labeled glucose derivatives for imaging tumor with SPECT,β-N-mercaptoacetyl-Val-Gly-Gly-glucose（MAVGG-Glu） was labeled with 99Tcm.The labelled compound was injected into the mice bearing S180 tumors,and biodistribution was measured at 3 h and 5 h postinjection.The biodistribution of 18F-2-fluoro-desoxy glucose（18F-FDG） at 5 h postinjection was also studied for comparison.The results showed that 99Tcm labeling yield was greater than 90%.The tumor uptakes at 3 h and 5 h postinjection were 1.46±0.41 and 1.28±0.24%ID/g,respectively.The T/NTs were greater than 1.8 for tumor over all other normal tissues excepted for kidney and liver at 5 h postinjection.T/NT of tumor to blood,tumor to muscle and tumor to brain were 4.41,4.00 and 8.53,respectively.Tumor was visualized at 3 h postinjection,and the contrast became slightly sharper with time lasted.The results suggested the potential utility of 99Tcm-MAVGG-Glu as a suitable tumor imaging agent.Compared with 18F-FDG,99Tcm-MAVGG-Glu had lower tumor uptake and T/NTs for most tissues.But its T/NTs for tumor to muscle,heart,spleen and brain,especially for tumor to brain,were higher,which indicated that 99Tcm-MAVGG-Glu may have advantages in imaging brain tumor and the tumor near brain.