~(99_Tc^m-octreotide在荷H22肝癌小鼠体内分布和显像研究  

Study of biodistribution and imaging for ^(99)Tc^m-octreotide in bearing H22 hepatocarcinoma mice

作　　者：张秀梅[1] 冯珏[1] 马慧莉[1] 王亚平[1] 王鹏[1] 杨新毅[1] 

机构地区：[1]河北医科大学第二医院核医学科,河北石家庄050000

出　　处：《中国医学影像技术》2006年第6期945-948,共4页Chinese Journal of Medical Imaging Technology

基　　金：河北省卫生厅基金资助(05009)

摘　　要：目的探讨99Tcmoctreotide作为生长抑素受体阳性肿瘤显像剂的可能性。方法99Tcmoctreotide的制备采用直接标记奥曲肽冻干品药盒的方法。①体内分布实验:25只正常KM小鼠和15只荷H22肝癌小鼠,静脉注射显像剂0.1ml(3.7MBq)后行常规体内分布实验,计算%ID/g及肿瘤的T/NT值。②荷瘤鼠显像:5只荷瘤鼠于注入显像剂后1、2、3、4、6h和24h不同时相分别显像并计算T/B值。结果①体内分布:正常小鼠体内分布显示,血液在0.5h放射性最高[(3.20±0.54)%ID/g],随后迅速清除。双肾1h摄取达最高[(13.62±4.83)%ID/g],提示显像剂主要经泌尿系统排泄。99Tcmoctreotide在荷瘤鼠的体内分布与正常小鼠一致,肿瘤与其他脏器组织的T/NT较高。②受体显像:注射显像剂1h后,小鼠全身轮廓清晰,肾和膀胱高度摄取显像剂,荷瘤鼠的已知肿瘤部位呈阳性显像。在2h肿瘤部位的放射性浓聚最高,显像效果最佳。随后放射性逐渐减弱,但肿瘤影像仍较清晰。24h时图像模糊。注射显像剂后1、2、3、4、6h和24h的T/B值分别为2.64、4.46、7.25、5.40、5.49和6.48,2h以后各时相与1h相比有显著性差异(P<0.05),但3h以后与前一时间点比较差异均无显著性(P>0.05)。结论一步法药盒制备的99Tcmoctreotide,在小鼠H22肝癌组织中分布快,消除较慢,靶和本底比值较高,注射后2h肿瘤显像最佳。99Tcmoctreotide是一种很有前景的生长抑素受体显像剂。Objective To evaluate the practicability of ^99Tc^m-octreotide as an imaging agent of somatostatin receptor-positive tumors. Methods Preparation of ^99 Tc^m-octreotide was that technetium-99m was labeled directly with cold-kit of octreotide. ①Animal biodistribution experiment： Twenty-five normal and fifteen tumor-bearing mice were injected with ^99 Tc^m- octreotide in 0.1 ml containing 3.7 MBq. The biodistribution was performed in routine methods and the percentage of radioactivity administered dose per gram of tissue （%ID/g） and target to non-target ratios （T/NT） at different interval were calculated.②Imaging of tumor-bearing mice： Five tumor-bearing mice were imaged respectively at 1, 2, 3, 4, 6, 24 h pi and calculated target to background ratios（T/B）. Results ①The normal mice biodistribution indicated that the blood radioactivity presented peak [（3.20±0. 54）%ID/g] at 30 min pi and ^99 Tc^m-octreotide were cleared rapidly thereafter. Physiological uptakes of kidney [（13.62±4. 83）% ID/g] were the highest at 1 h pi and showed the radio pharmaceutical excreted mostly by kidney. The in vivo distribution of bearing-tumor mice was similar to normal mice. The tumor T/NT were higher and reached to （6.44±0.20） at 2 h pi. ②Receptor scintigraphy showed that the imaging of mice outline were clearly seen at 1 h pi. The radioactivity uptake in kidneys and bladder were very highly too. Known tumor sites showed rapid and intense tracer accumulation. The tumor imaging was high quality at 2 h and then gradually unclear from time to time. Up to 24 h, the imaging was blurred; The T/B were 2.64, 4.46, 7.25, 5.40, 5.49 and 6.48 at 1, 2, ：3, 4, 6, 24 h respectively. The T/B was raised rapidly from 1 h to 2h and 3h, and the difference was significant between that of 1 h and other times （P〈0.05）. After 3 h, the uptake change was not obvious with time. Conclusion The distribution of ^99Tc^m-octreotide by one step method labeled in bearing-tumor mice is very quickly, extinction is slower rel

关 键 词：生长抑素受体 奥曲肽 核素显像 小鼠 生物分布 

分 类 号：Q95-33[生物学—动物学] R730.44[医药卫生—肿瘤]