George E A, Hendershott L R, Klos D J, Donati R M
Eur J Nucl Med. 1980 Jun;5(3):241-5. doi: 10.1007/BF00271906.
Hepatic extraction, cellular and subcellular localization of gelatin stabilized Tc-99m sulfur colloid was studied in the rat model with time sequenced microautoradiography from 15 min to 24 h following I.V. administration of the tracer. Hepatic lobular and cellular distribution, quality and quantity of focal grain pattern, grain clusters, remained essentially constant for the period of study. Grain clusters were associated predominantly with Kupffer cells lining the peripheral segment of hepatic lobular sinusoids. Subcellular localization of gelatinized Tc sulfur colloid, stained prior to the I.V. administration with osmium tetroxide, was demonstrated with a transmission electron microscope in unosmicated liver tissue. Extracted Tc sulfur colloid particles were attached in groups to cytoplasmatic membranous intrasinusoidal projections of activated Kupffer cells. Intracytoplasmatic phagocytosis was not demonstrated. The kinetic arrest and en groupe extraction of Tc sulfur colloid particles at the Kupffer cell membrane suggests a specific membrane receptor site and specific Tc sulfur colloid particle-plasma protein interaction at the time of extraction. Hepatic extraction of gelatinized Tc sulfur colloid thus reflects primarily extra and intra hepatic hemodynamics and does not serve as an indicator of phagocytic hepatic reticuloendothelial system function.
在大鼠模型中，通过静脉注射示踪剂后15分钟至24小时的时间序列显微放射自显影，研究了明胶稳定的锝-99m硫胶体的肝脏摄取、细胞和亚细胞定位。在研究期间，肝小叶和细胞分布、局灶性颗粒模式的质量和数量、颗粒簇基本保持不变。颗粒簇主要与肝小叶窦周缘的库普弗细胞相关。在静脉注射前用四氧化锇染色的明胶化锝硫胶体的亚细胞定位，通过透射电子显微镜在未染色的肝组织中得以证实。提取的锝硫胶体颗粒成组附着在活化的库普弗细胞的细胞质膜内窦状突起上。未观察到胞质内吞噬作用。锝硫胶体颗粒在库普弗细胞膜上的动力学停滞和成组摄取表明在摄取时存在特定的膜受体位点和特定的锝硫胶体颗粒-血浆蛋白相互作用。因此，明胶化锝硫胶体的肝脏摄取主要反映肝内外血流动力学，而不是作为吞噬性肝网状内皮系统功能的指标。
