心脏肾上腺素能神经的PET应用

目的研究188Re-奥曲肽在荷瘤裸鼠体内的分布,为进一步肿瘤靶向治疗奠定基础。方法16只荷人H460非小细胞肺癌的BALB／c裸鼠分为4组,经尾静脉注射188Re-奥曲肽 18．5MBq(O．2ml)．于注射后2h,4h,24h,48h每个时间点处死一组裸鼠,取血液、肿瘤组织及主要脏器测量其放射性计数率值,经放射性衰变校正后计算每克组织的百分注射剂量率(％ID／g),观察标记物在动物体内的生物学分布。另2只荷瘤裸鼠同样尾静脉注射相同剂量的188Re-奥曲肽,于注射后相同时间点行SPECT扫描,利用感兴趣区技术对肿瘤／非瘤组织放射性比值(T／NT)进行半定量分析。结果188Re-奥曲肽标记率达(95．3±1．8)％,188Re-奥曲肽在荷瘤裸鼠体内主要分布于肿瘤组织、肝脏、肾脏及肠道,肿瘤部位在4h摄取达到高峰9．8％ID/g,此时SPECT在肿瘤部位有明显的放射性核素浓聚,T／NT在尾静脉药物注射后24h达到高值为7．1。结论 188Re-奥曲肽在BALB／c荷瘤裸鼠体内对人非小细胞肺癌具有靶向定位作用,其在肿瘤部位的分布具有较高的T／NT,188Re．奥曲肽有望用于表达生长抑素受体肿瘤的核素靶向治疗。

Application of cardiac neurotransmission PET imaging

Objective To study the biodistribution of 188Re-octreotide in nude mice which bear-ing human H460 non-small-cell lung cancer and to establish the laying foundation of targeting therapy. Methods 188Re-octreotide was injected through tail vein of 16 nude mice, those nude mice were killed and the tumors and major organs were taken out from those mice at 2h, 4h, 24h and 48h after injection, then the radioactivity count of those organs and tumors were measured. Other two nude mouse were injected the same dosage 188Re-octreotide too, SPECT scanning and using regoin of interest technique for semi-quantitative analysis of main organs and tumors'uptake at 2h, 4h, 24h and 48h after injection. Results It was found that the labeling efficiency of 188Re-octreotide was (95.3 ?1.8)%. 188Re-octreotide was major distributed in tumors, lives, small bowels, large bowels and kidneys in nude mice. The largest uptake of tumors is 9.8%ID/g at 4h after injection and the largest tumor/muscle ratios in the SPECT study in those nude mice is 7.1 at 24h after injection. Conclusion The results indicated that 188Re-octreotide can be located to those tumors which high expressed somatostatin receptor. The tumor/muscle ratios in nude mice is so high that expect to be used for targeting therapy of human H460 non-small-cell lung cancer.