Grover P K, Ryall R L, Marshall V R
Department of Surgery, Flinders Medical Centre, Bedford Park, South Australia.
Clin Chim Acta. 1990 Oct 15;190(3):223-38. doi: 10.1016/0009-8981(90)90176-s.
Using two different experimental techniques, Tamm-Horsfall mucoprotein (THM) has been reported both to inhibit and to promote calcium oxalate (CaOx) crystallization in ultrafiltered human urine. In this study, these two techniques were used to compare the effects of THM on CaOx crystallization in the same ultrafiltered urine samples. Urine was collected from 10 healthy men and ultrafiltered (10,000 Da). Each sample was divided and to one half was added sufficient human THM to give a final concentration of 35 mg/L. CaOx crystallization was induced in the samples by addition of an oxalate load and by evaporation. Using the evaporation technique THM significantly increased the deposition of CaOx determined as 14C-oxalate, from 9,772 cpm to 43,652 cpm (P less than 0.01). Using the oxalate load method THM had no effect on the metastable limits of the urine with respect to CaOx, and significantly increased the volume of particulate material deposited from 26,000 to 39,995 microns 3/microliters - an increase of 54%. This increase was reduced to 21% when values were corrected for the volume of THM particles recorded in control samples to which no oxalate load was added. Using 14C-oxalate, it was shown that this increase in volume could not be attributed to an enhanced deposition of crystalline CaOx, but was probably the result of an increased polymerization of THM in the presence of CaOx crystals. Despite this, the average size of the particles precipitated in the presence of THM (6.5 microns) was significantly (P less than 0.01) less than that observed in the absence of THM (12.1 microns). It was concluded that the effect of THM on CaOx crystallization in urine depends upon the methodology used to assess it and that promotion would only be expected in vivo in cases of extreme dehydration. Under usual physiological conditions THM would be expected to inhibit CaOx crystal aggregation and to have little effect, if any, on the amount of crystalline material deposited.
运用两种不同的实验技术，有报告称，在超滤后的人尿中，Tamm-Horsfall黏蛋白（THM）既能抑制草酸钙（CaOx）结晶，又能促进其结晶。在本研究中，使用这两种技术比较了THM对相同超滤尿样中CaOx结晶的影响。从10名健康男性收集尿液并进行超滤（截留分子量10,000道尔顿）。将每个样品分成两份，向其中一份加入足量的人THM，使其终浓度达到35 mg/L。通过添加草酸盐负荷并蒸发来诱导样品中的CaOx结晶。使用蒸发技术时，THM显著增加了以14C-草酸盐测定的CaOx沉积量，从9,772 cpm增加到43,652 cpm（P小于0.01）。使用草酸盐负荷法时，THM对尿液相对于CaOx的亚稳极限没有影响，且显著增加了沉积的颗粒物质体积，从26,000增加到39,995立方微米/微升，增加了54%。当对未添加草酸盐负荷的对照样品中记录的THM颗粒体积进行校正后，这一增加幅度降至21%。使用14C-草酸盐表明，这种体积增加并非归因于结晶CaOx沉积的增强，而可能是在CaOx晶体存在下THM聚合增加的结果。尽管如此，在THM存在下沉淀的颗粒平均尺寸（6.5微米）显著（P小于0.01）小于未添加THM时观察到的尺寸（12.1微米）。得出的结论是，THM对尿液中CaOx结晶的影响取决于用于评估它的方法，并且仅在极度脱水的情况下才有望在体内起到促进作用。在通常的生理条件下，预计THM会抑制CaOx晶体聚集，并且对沉积的结晶物质数量几乎没有影响（如果有影响的话）。
