钐在小鼠肝脏细胞中的动态观察

本实验给小鼠一次静脉注射氯化钐(70mg/kg体重)后15min至48h中的不同间期,应用电镜与X射线微区分析术对钐在肝脏枯否细胞与肝细胞中的运转进行了动态追踪。于15min 至2 h,两种细胞均以胞吞方式摄入含钐微粒,在胞质中形成吞噬体。在吞噬体中,微粒群处于由稀疏至密集的浓缩过程。小吞噬体亦互相融合。这种胞吞作用于枯否细胞极为活跃。于4—24 h,很多枯否细胞胞质充满吞噬体,细胞已经或趋于变性、崩解。肝细胞内的吞噬体则汇集于胆小管周围。于胆小管腔中可见到高电子密度微粒群,表明体内钐可经胆汁途径排出。于48 h,两种肝脏细胞巾仍见钐吞噬体沉积。

A DYNAMIC OBSERVATION ON THE FATE OF SAMARIUM IN MOUSE LIVER

It is generally considered that the rareearth compounds are plasmamembrane-im-permeable,thus affecting the cells only ontheir surface.Recently,we found that afterrepeated injections to mice of large dose ofsamarium trichloride,a soluble compoundof rare earth,samarium aggregates appearedin Kupffer cells and hepatocytes of liver.In this study,we aimed at observingthe route by which samarium enters theliver cells and the process of the formationof samarium aggregates.Samarium trichloride was given toSwiss mice at one dose of 70 mg/kg intra-venously.Thereafter,at different intervalsfrom 15 min to 48h after the injection,the samarium in liver was traced dynami-cally by electron microscopy and X raymicroanalysis.From 15 min to 2h bothKupffer cells and hepatocytes endocytosedsamarium-containing particles and formedphagosomes,in which the ingested particleswere progressively concentrated.Besides,the small phagosomes fused with eachother,phagocytosis was especially active inKupffer cells.During the 4h to 24h manyKupffer cells were degenerated and broken.In hepatocytes the phagosomes gatheredmostly around the bile canaliculi.Groupsof highly electron-dense particles werefound in the lumen of bile canaliculi,implying the excretion of samarium by bile.At the 48h,the samarium-containingphagosomies were found still in both kindsof cells in the liver.