铁蛋白受体放射配体结合分析法

本文采用差速离心法制备胎盘微绒毛膜，用125I－Hunter试剂联接标记铁蛋白，在国内首次建立了胎盘微绒毛膜铁蛋白受体放射配体分析法，并进行了最适反应条件及铁蛋白受体的特性研究。所标记的125I一铁蛋白放化纯达95％以上，且免疫活性和生物活性均较好。用放射配体受体分析测定了11例正常足月孕妇胎盘微绒毛膜铁蛋白受体数为（3．534土1．105）×1012位点／毫克膜蛋白，亲和力常数Ka为（2．203土0．622）×107mol-1．L。实验条件为：膜蛋白160ug，125I互铁蛋白与游离铁蛋白分离的PEG浓度为12％。对铁蛋白受体特性研究表明：铁蛋白受体与铁蛋白结合具有高度特异性、可饱和性和中度亲和力。

THE RADIOLI GAND ASSAY ON HUMAN PLACENTAL FERRITIN RECEPTOR

Using the human placental microvillous membrane as the receptor reagent and Na125Iapo--Fr as the radioligand , the receptor radioligand asay (RRA) of ferritin receptor (FrR)was first established in our country. The microvillous membrane was isolated by the differential centrifugation, Na 125I--apo--Fr was labelled by modified 125I--Hunter conjugation labelling method. the experimental condition and the characteristic of FrR were also studied.The radiochemical purity of 125I--apo--Fr was above 95% and immunologic competence andbiological activity of 125I--apo --Fr were better. The analysis of FrR expression on placentswas one in 11 cases of normal term pregnant women. The result indicated that the FrR expression was (3. 534± 1. 105) X 1012, sites/mg. pro; Ka: (2. 203±0. 622) X 107 mol-1. L.the experimental condition were as following: the memberane protein 160mg, 125I--apo--Fr 0.lug, the receptor--bound ferritin and free ferritin were separated by polyethy--lenegly 12%The study of FrR characteristic revealed that the FrR binding Fr is of very high specificity,saturation, and moderate affinity.