Nakagawa Y, Abram V, Coe F L
Am J Physiol. 1984 Nov;247(5 Pt 2):F765-72. doi: 10.1152/ajprenal.1984.247.5.F765.
Glycoproteins that slow the growth rate of calcium oxalate monohydrate crystals were purified from rat kidney homogenate and urine by selective heat denaturation (for rat kidney homogenate), DEAE-cellulose column chromatography, and gel permeation column chromatography. Both kidney and urine inhibitors were glycoproteins with an apparent mol wt of 1.4 X 10(4), as determined by high-performance liquid chromatography. They contained gamma-carboxyglutamic acid and a high percentage of aspartic acid and glutamic acid but had few aromatic amino acid residues. Both inhibitors contained fucose, mannose, glucose, galactose, glucosamine, galactosamine, and N-acetylneuraminic acid but no glucuronic acid. Kinetic studies suggest that purified inhibitors bind to calcium oxalate monohydrate seed crystals according to a Langmuir adsorption isotherm with similar dissociation constants of 14 X 10(-8)M for rat urine inhibitor and 8.7 X 10(-8) M for rat kidney inhibitor. The isolation of similar glycoproteins from kidney and urine suggests that urinary crystal growth inhibitor may be produced in the kidneys.
通过选择性热变性（用于大鼠肾脏匀浆）、DEAE - 纤维素柱色谱和凝胶渗透柱色谱，从大鼠肾脏匀浆和尿液中纯化出了减缓一水合草酸钙晶体生长速率的糖蛋白。通过高效液相色谱测定，肾脏和尿液中的抑制剂均为糖蛋白，表观分子量为1.4×10⁴。它们含有γ - 羧基谷氨酸以及高比例的天冬氨酸和谷氨酸，但芳香族氨基酸残基较少。两种抑制剂都含有岩藻糖、甘露糖、葡萄糖、半乳糖、氨基葡萄糖、半乳糖胺和N - 乙酰神经氨酸，但不含葡萄糖醛酸。动力学研究表明，纯化后的抑制剂根据朗缪尔吸附等温线与一水合草酸钙籽晶结合，大鼠尿液抑制剂的解离常数类似，为14×10⁻⁸M，大鼠肾脏抑制剂的解离常数为8.7×10⁻⁸M。从肾脏和尿液中分离出相似的糖蛋白表明，尿液晶体生长抑制剂可能在肾脏中产生。
