The immplication of crystal surface binding substances (CSBS) on urinary stone formation.

泌尿大分子被认为在结石形成中起重要作用。我们研究的目的是表征影响结石形成的尿蛋白。在人全尿中加入钙和草酸盐，得到晶体表面结合物质（CSBS）。CSBS是尿液大分子吸附在草酸钙晶体表面，对草酸钙结晶有较强的抑制作用。分析CSBS中所含的蛋白质。DEAE-Sepharose CL-6B离子层析获得了具有强草酸钙晶体生长抑制活性的富蛋白组分。这些馏分用羟基磷灰石柱分馏，磷酸钠逐步洗脱。SDS-PAGE显示了许多蛋白质条带。用氨基酸测序仪分析分子量为30Kd和67Kd的两种主要蛋白。因此，30Kd蛋白与人凝血酶原一致，67Kd蛋白与人骨桥蛋白一致。用免疫印迹法分析羟基磷灰石柱获得的蛋白质组成。检测人血清白蛋白、α 1-酸性糖蛋白、α 1-微球蛋白、α 2-HS糖蛋白、视黄醇结合蛋白、转铁蛋白、Tamm-Horsfall黏蛋白和凝血酶原。然而，人们认为这些蛋白质对草酸钙晶体的形成并没有显著的作用，因为含有这些蛋白质的每个组分对晶体生长的抑制能力都很弱。我们得出结论，CSBS中包含的其他未知蛋白被认为是显性蛋白抑制剂。

Urinary macromolecules are considered to play a important role in stone formation. The aim of our study is to characterize the urinary protein affecting stone formation.1.We obtained crystal surface binding substance (CSBS) by adding calcium and oxalate to human whole urine. The CSBS is urinary macromolecules absorbed onto the surface of calcium oxalate crystals and yields strong inhibitory activity on calcium oxalate crystallization. Proteins contained in the CSBS are analyzed.2.Fractions enriched in proteins with strong calcium oxalate crystal growth inhibitory activity are obtained by DEAE-Sepharose CL-6B ion-chromatography. These fractions are fractionated by hydroxyapatite column with stepwise elution of sodium phosphate.3.The SDS-PAGE shows many bands of protein. Two major proteins, molecular weight of 30Kd and 67Kd, are analyzed by a amino acid sequencer. As a result, 30Kd protein is identified with human prothrombin and 67Kd protein with human osteopontin.4.Protein composition of fractions obtained by hydroxyapatite column is also analyzed by immunoblotting. Human serum albumin, alpha 1-acid glycoprotein, alpha 1-microglobulin, alpha 2-HS glycoprotein, retinol-binding protein, transferrin, Tamm-Horsfall mucoprotein and prothrombin are detected. However, it is considered that these proteins does not play a signifficant role on calcium oxalate crystal formation because each fractions containing each proteins reveal weak inhibitory power on crystal growth.We conclude that other unknown proteins included in CSBS are thought to be dominant protein inhibitors.