Ehrlich K, Holland F, Turnham T, Klein E
Clin Nephrol. 1980 Jul;14(1):31-5.
Hemofiltrate from uremic patients was concentrated 15- to 40-fold by osmotic removal of water across a reverse osmosis membrane which retains salts and proteins. Salts and low molecular weight components were removed from the concentrate by partial dialysis using a highly impermeable cellulose membrane. Following this desalting step, 100- to 500-fold concentration could be achieved by evaporation at low pressure. The concentrate was fractionated on Sephadex G15 columns. Fractions were tested for their toxicity to human cells in culture. Fractions containing components with molecular weights greater than 700 daltons inhibited 3H-thymidine incorporation into the DNA of HeLa and skin fibroblast cells more than did low molecular weight peptides and an iso-osmolar control. Components eluting in the molecular weight range of angiotensin I and vitamin B-12 were most inhibitory. These studies show that hemofiltrate from uremic patients is a readily available source of toxic polypeptides. The osmotic concentration and gel chromatographic procedures described should make available large amounts of these molecules for further studies.
通过反渗透膜以渗透方式去除水分，可将尿毒症患者的血液滤过液浓缩15至40倍，该膜可保留盐分和蛋白质。使用高度不透性的纤维素膜通过部分透析从浓缩物中去除盐分和低分子量成分。在这个脱盐步骤之后，通过低压蒸发可实现100至500倍的浓缩。将浓缩物在Sephadex G15柱上进行分级分离。检测各馏分对培养中的人类细胞的毒性。与低分子量肽和等渗对照相比，含有分子量大于700道尔顿成分的馏分对3H-胸腺嘧啶核苷掺入HeLa细胞和皮肤成纤维细胞DNA的抑制作用更强。在血管紧张素I和维生素B - 12分子量范围内洗脱的成分抑制作用最强。这些研究表明，尿毒症患者的血液滤过液是有毒多肽的现成来源。所描述的渗透浓缩和凝胶色谱程序应能提供大量这些分子以供进一步研究。
