Detection of apolipoprotein C in human and rat enterocytes
Detection of apolipoprotein C in human and rat enterocytes
复制标题
人和大鼠肠细胞中载脂蛋白 C 的检测
作者：
G. Schonfeld;N. Grimme;D. Alpers
载脂蛋白在脂蛋白代谢中具有重要的生理功能。在肠道中产生几种载脂蛋白，包括ApoA-I、ApoA-IV和ApoB。每一种似乎都参与肠道脂质转运。肝脏也产生几种载脂蛋白，包括ApoC-II和ApoC-III，但证明肠道产生ApoC的能力的数据是不完整的。我们的目的是确定ApoC-II和ApoC-III是否存在于人类和大鼠空肠中，如果存在，它们的存在是否会因脂肪喂养而改变。应用免疫定位技术和新近建立的大鼠ApoC-Ⅲ 3双抗体放射免疫分析法。ApoC-III 3被发现在肠上皮细胞的核上区域沿着整个长度的绒毛在空肠的12小时禁食大鼠。胃摄入玉米油后1小时。ApoC-III 3主要存在于细胞之间和固有层中。在人空肠活检中使用ApoC-II和ApoC-III获得了类似的结果。ApoC-III 3也通过放射免疫法在分离自新生和成年大鼠空肠的肠细胞中检测到。因此，ApoC-II和ApoC-III明显存在于肠以及肝脏中。此外，由于它们的定位在脂肪喂养后改变，它们也可能在肠上皮细胞中产生。
Apoproteins have important physiologic functions in lipoprotein metabolism. Several apoproteins are produced in the intestine including ApoA-I, ApoA-IV, and ApoB. Each appears to participate in intestinal lipid transport. The liver also produces several apoproteins, including ApoC-II and ApoC-III, but the data demonstrating the ability of the intestine to produce ApoC is incomplete. Our aim was to ascertain whether ApoC-II and ApoC-III were present in human and rat jejunum, and if so, whether their presence was altered by fat feeding. The technique of immunolocalization and a newly developed double antibody radioimmunoassay for rat ApoC-III3 were used. ApoC-III3 was found in the supranuclear regions of enterocytes along the entire lengths of villi in the jejuna of 12-h-fasted rats. 1 hour after the gastric ingestion of corn oil. ApoC-III3 was found primarily in between cells and in the lamina propria. Similar results were obtained in human jejunal biopsies with ApoC-II and ApoC-III. ApoC-III3 was also detected by radioimmunoassay in enterocytes isolated from jejuna of neonatal and adult rats. Thus, ApoC-II and ApoC-III are clearly present in the intestine as well as in the liver. In addition, because their localization is altered after fat feeding, they are also likely to be produced in the enterocyte.