Utsunomiya M, Koide T, Yoshioka T, Yamaguchi S, Okuyama A
Department of Urology, Osaka University Medical School, Japan.
Br J Urol. 1993 May;71(5):516-22. doi: 10.1111/j.1464-410x.1993.tb16017.x.
We investigated the influence of ionic strength on both the binding ability of macromolecules onto calcium oxalate crystals and the inhibitory activity of macromolecules related to calcium oxalate crystal growth and aggregation in vitro. The amount of heparin sodium salt adsorbed onto calcium oxalate crystals was studied in both a seed and a non-seed crystal system at various ionic strengths with the aid of radiolabelled heparin. In both adsorption models, adsorption of heparin was greater in the buffered solutions of lower ionic strength, and significantly so in the range of physiological ionic strength. The inhibitory activity of heparin in the non-seed crystal system, which was determined using a Coulter Multisizer, increased as the adsorbed dose increased. The naturally existing urinary macromolecules showed a similar change in their inhibitory activity on calcium oxalate crystal growth and/or aggregation in accordance with changes in ionic strength. These results indicate that macromolecular inhibitory activity seems to be enhanced in urine of lower ionic strength as a result of an increased adsorption of macromolecules on the surface of calcium oxalate crystals.
我们研究了离子强度对大分子在草酸钙晶体上的结合能力以及大分子在体外与草酸钙晶体生长和聚集相关的抑制活性的影响。借助放射性标记的肝素，在不同离子强度下的晶种和非晶种晶体体系中研究了吸附在草酸钙晶体上的肝素钠盐的量。在两种吸附模型中，肝素在较低离子强度的缓冲溶液中的吸附量更大，在生理离子强度范围内尤为显著。使用库尔特多参数分析仪测定，在非晶种晶体体系中，肝素的抑制活性随吸附剂量的增加而增强。天然存在的尿液大分子对草酸钙晶体生长和/或聚集的抑制活性也随着离子强度的变化呈现出类似的变化。这些结果表明，由于大分子在草酸钙晶体表面的吸附增加，在较低离子强度的尿液中，大分子的抑制活性似乎增强。
