【摘要】 为了降低鸟亲和素（Ａｖ）的高肝摄取，延长Ａｖ在血液中的滞留时间，对Ａｖ进行化学修饰。修饰后的Ａｖ衍生物用１２５Ｉ标记示踪，观察小鼠体内生物分布。结果表明，Ａｖ衍生物１２５Ｉ－ｓｕｃ－Ａｖ减少肝、肾、脾中摄取最佳；衍生物１２５Ｉ－ｏｃｔｏ－Ａｖ在肾中摄取较链霉亲和素低，而在肝中仍有较高放射性浓集；衍生物１２５Ｉ－ｏｃｔｏ－Ａｖ－ｓｕｃ的肾摄取虽较高，但代谢较１２５Ｉ－ＳＡ快，然而肝摄取没有明显降低。三种Ａｖ衍生物的血中放射性都低于Ａｖ。更多还原

【Abstract】 ? In order to decrease the high liver uptake of avidin(Av), and elongate its retention in blood, Av is modified with some chemical groups. The tissue distributions in mice of Av, sucAv, octoAv, octoAvsuc, streptavidin(SA), all of which are labelled with 125 I, are studied at 3,6,16,26h post injection. It is shown that 125 IsucAv lowers the uptake in liver, kidney and spleen, and 125 IoctoAv has lower uptake than 125 ISA, but the radioactivity in liver is high; the kidney concentration of 125 IoctoAvsuc is the highest at first, however, its metabolism in kidney is quicker than 125 ISA. The blood levels of 125 IsucAv, 125 IoctoAv, 125 IoctoAvsuc, are lower than that of 125 IAv.更多还原