^(131)I在细胞水平分布的实验研究

An experimental study of ^(131)I microdistribution at cellular level

目的用131I放射自显影技术观察其在细胞水平的分布,探讨放射性药物效果预测及评价。方法采用放射自显影和冷冻切片技术,建立银颗粒密度与放射性药物强度的刻度曲线,确定放射性药物131I的微观分布,基于核素的微观分布数据,建立微剂量的剂量估算模式。结果银颗粒密度与施入放射性药物比活度的相关系数为0·9963,刻度系数为1·59×10-4Bq。结论131I在细胞水平的分布是不均匀的,银颗粒多数是分布在细胞浆中。因此在计算细胞水平的剂量时应考虑到其分布的不均匀性。

Objective Traditional MIRD method for dose assessment in nuclear medicine assumes that radionuclide is homogeneously distributed in organs,the dose to cell and cell nucleus is presented by the mean dose to the organ.However,this assumption is hardly satisfication because of various factors,such as nuclide and its carrier ,organ/cell and so on.Understanding micro-dose（i.e.,doses at cell ,meta-cell and molecule levels ）distribution of radionuclide is an essential element for stipulating detailed plan for diagnosis and treatment in clinical nuclear medicine,as well as an important factor for predicting and assessing radio-pharmaceuticals effect.Method In this work ,the micro distribution of ^131Ⅰis deseribed using microautoradiogtraphy and frozen seetioning lechnique.Results to describe the relationship belween argent grain density and nuclide radioactivity a regression curve was depicted,and the Rvalue calculated was 0.9963.The scale coefficient of argent grain was 1.59×10^-4 Bq.Conclusion The distribution of radiomedicament ^131Ⅰat cellular level is nomuniform.