应用^(99m)Tc-NGA进行肝ASGP受体显像的实验研究

Hepatic ASGP receptor image of ^(99m)Tc-NGA in normal rabbit

新半乳糖人血清白蛋白（ＮＧＡ）是肝细胞表面去唾液酸糖蛋白受体（ＡＳＧＰＲ）的特异性配基。根据受体与配基结合的原理，报道了以９９ｍＴｃ标记的ＮＧＡ与人血清白蛋白（ＨＳＡ）在正常兔中显像行为的对比。结果表明９９ｍＴｃ－ＨＳＡ呈现血池显像剂的行为，而９９ｍＴｃ－ＮＧＡ则呈现肝脏受体显像剂的行为，并且若兔事先用１００倍量未标记的ＮＧＡ将肝脏受体饱和后，再用９９ｍＴｃ－ＮＧＡ显像则呈现与９９ｍＴｃ－ＨＳＡ相似的显像结果。以异硫氰酸荧光素标记的ＮＧＡ（ＦＩＴＣ－ＮＧＡ）进行流式细胞分析（ＦＣＭ）也表明，ＡＳＧＰＲ具有明显可饱和性。由此进一步表明９９ｍＴｃ－ＮＧＡ是ＡＳＧＰ受体显像，而非胶体显像；且具有饱和性．

Galactosylneoglycoalbumin (NGA) is aspecific ligand of asialoglycoproteinreceptor (ASGPR) in hepatocyte surface.In this paper,the imaging comparison of^99mTc-NGA and ~99mTc-HSA in normal rabbit imaging are reported. ~99mTo-HSAgenerated a blood pool image when injected into normal rabbit, while ~99mTo-NGAshowed a hepatic receptor image charateristics. If rabbit hepatic receptor had beensaturated with 100 times amounts of NGA, ~99mTc-NGA would generate a blood poolimaging sunilar to ~99mTc-HSA. Flow cytometry (FCM) analysis with FITC-NGA alsoshowed that ASGPR could be obviously saturated. Therefore, ~99mTc-NGA is ahepatic receptor image agent.