Komori T, Yoshimura M, Inoue H, Suzuki K, Yasumura T, Morimoto T
Clinical Laboratory Unit of University Hospital, Kyoto Prefectural University of Medicine, Japan.
Rinsho Byori. 1996 May;44(5):477-82.
Urinary free dopamine (DA) is derived from DA synthesized or converted from circulating DOPA in renal proximal tubules, and plays an important role for diuresis and natriuresis. As plasma free DA is in tiny amounts near detectable range, a large amount of free DA in urine is tubular origin, but not from circulating DA. In the present study, we hypothesized that urinary free dopamine (U-f-DA) can be used as the marker of renal function. We speculated that U-f-DA may decrease in the damage of renal tubules or renal disorder. To evaluate clinical significance of U-f-DA, we used serum creatinine levels as the index of renal function. As the urinary parameter of renal function, we measured U-f-DA, alpha(1)-microglobulin (U-alpha(1) MG), beta(2)-microglobulin (U-beta(2)MG) and N-acetyl-beta-D-glucosaminidase (U-NAG) in spot urine samples of 154 outpatients (male; 76, female; 78). Each values are rectified by creatinine (Cr) concentration in urine. U-f-DA was negatively correlated with the serum level of creatinine, U-alpha(1)MG and U-beta(2)MG. The receiver operating characteristic (ROC) curve analysis was used for their comparison in evaluation of urinary marker of renal function. In this analysis, area under the curve (AUC) of U-f-DA is best among other markers of renal function. AUC of U-f-DA/Cr, U-alpha(1)MG/Cr, U-beta(2)MG/Cr, U-NAG/Cr were 0.82, 0.57, 0.72, 0.62 in male, 0.92, 0.72, 0.81, 0.57 in female, respectively. These results suggest that the measurement of U-f-DA is superior marker of renal function to the determination of U-alpha(1)MG, U-beta(2)MG and U-NAG.
尿游离多巴胺（DA）源自肾近端小管中由循环多巴合成或转化而来的DA，对利尿和利钠起着重要作用。由于血浆游离DA含量极少，接近可检测范围，尿液中的大量游离DA源自肾小管，而非循环中的DA。在本研究中，我们假设尿游离多巴胺（U-f-DA）可作为肾功能的标志物。我们推测在肾小管损伤或肾脏疾病时U-f-DA可能会降低。为评估U-f-DA的临床意义，我们将血清肌酐水平作为肾功能指标。作为肾功能的尿液参数，我们在154例门诊患者（男性76例，女性78例）的随机尿样中测量了U-f-DA、α1-微球蛋白（U-α1MG）、β2-微球蛋白（U-β2MG）和N-乙酰-β-D-氨基葡萄糖苷酶（U-NAG）。每个值均通过尿肌酐（Cr）浓度进行校正。U-f-DA与血清肌酐水平、U-α1MG和U-β2MG呈负相关。采用受试者工作特征（ROC）曲线分析对它们在评估肾功能尿液标志物方面进行比较。在此分析中，U-f-DA的曲线下面积（AUC）在其他肾功能标志物中最佳。男性U-f-DA/Cr、U-α1MG/Cr、U-β2MG/Cr、U-NAG/Cr的AUC分别为0.82、0.57、0.72、0.62，女性分别为0.92、0.72、0.81、0.57。这些结果表明，与测定U-α1MG、U-β2MG和U-NAG相比，测量U-f-DA是更好的肾功能标志物。
