18F-氟赤式硝基咪唑肿瘤乏氧显像实验研究

目的 探讨18F-氟赤式硝基咪唑(FETNIM)在肿瘤乏氧诊断中的应用价值.方法 30只SPCA-1人肺腺癌荷瘤BALB/c裸鼠采用随机数字表法分为A和B 2组(鼠数分别为16和14只).尾静脉注射37 MBq18F-FETNIM后A组分别于注射后0.5,1,2,3 h处死裸鼠,取血液、肺、心、肝、脾、肾、肿瘤等组织测量质量,用γ计数仪测定放射性计数,计算每克组织百分注射剂量率(%ID/g);B组用PO2微电极测量肿瘤组织内乏氧情况.结果 18F-FETNIM在肾中代谢最高,在脂肪和骨骼中代谢较低,肿瘤/正常组织的放射性比值较高,且随时间而增加,2 h达最高,肿瘤/血液放射性比值为1.69±0.37,肿瘤/肌肉放射性比值为1.57±0.47.HE染色显示瘤内有大量的乏氧坏死组织.组织内PO2微电极测量示肿瘤内均有乏氧,肿瘤内PO,1.1～27.7 mm Hg(1 mm Hg=0.133 kPa).结论 18F-FETNIM在荷瘤裸鼠体内具有较低的外周代谢,脂溶性较低,能被肿瘤乏氧组织摄取,可用于肿瘤乏氧诊断.

Hypoxic agent of 18F-flurorerythronitroimidazole in human lung adenocarcinoma cell line

Objective The aim of this study was to investigate the value of18F-fluoroerythronitromidazole(FETNIM)in detecting tumor hypoxia in vivo.Methods BALB/c nude mice were xenografted with SPCA-1 lung cancer cells.Tumors were allowed to grow to a diameter about 10 mm.In group A (n=16),18F-FETNIM(37 MBq)was injected from tail vein.Biodistribution of 18F-FETNIM was studied at 0.5,1,2,and 3 h after tracer injection.Blood,muscle,heart,liver,kidney,fat,lung,and tumor were moved and weighted.The radioactivity was measured with percentage activity of injection dose per gram of tissue(%ID/g)by a γ-counting well.In group B(n=14),the intratumoral PO2 measurements were obrained by polar graphic oxygen needle probe.Results The radioactivity was highest in kidney and lowest in fat and bone matrix.The maximum tumor to blood(T/B)and tumor to muscle(T/M)ratios were 1.69±0. 37 and 1.57±0.47 at 2 h after injection.Intratumoral PO2 measurements were ranged from 1.1 to 27.7 mm Hg (1 mm Hg=0.133 kPa)and were 30.2 to 40.5 mm Hg for normal tissue.Conclusion A relatively high 18F-FETNIM retention ratio indicated18F-FETNIM to be a potential agent for detecting tumor hypoxia in vivo.