Ritter M, Geiseler D
Methods Find Exp Clin Pharmacol. 1983 Jul-Aug;5(6):403-6.
Although only less than 1% of the daily secreted cortisol is excreted unchanged into urine, the determination of urinary cortisol has proved to be a valuable parameter in evaluation of adrenocortical function. We compared the procedures of cortisol determination by radioimmunoassay after extraction and without extraction direct in crude urine. Direct determination needs less tracer and antibody and is less laborious. Intra- and interassay variance is 4.5%, 16.0% in the extraction method and 2.7%, 8.2% in the direct method, respectively. Comparison of both methods is acceptable (r = 0.92), recovery and dilution studies prove the direct method to be correct. Despite a lowered specificity, which gives higher results (factor 1.7) compared to the extraction method, the direct method is entirely sufficient for routine laboratory purposes. It can be achieved without additional equipment by laboratories, which determine total cortisol concentration in plasma.
虽然每日分泌的皮质醇仅有不到1%以原形排泄到尿液中，但尿皮质醇的测定已被证明是评估肾上腺皮质功能的一个有价值的参数。我们比较了提取后用放射免疫分析法测定皮质醇的方法与直接在粗尿中不提取直接测定的方法。直接测定所需的示踪剂和抗体较少，且操作更简便。提取法的批内和批间变异分别为4.5%、16.0%，直接法的批内和批间变异分别为2.7%、8.2%。两种方法的比较结果是可接受的（r = 0.92），回收率和稀释研究证明直接法是正确的。尽管直接法的特异性较低，与提取法相比结果偏高（系数为1.7），但直接法对于常规实验室检测来说完全足够。能够测定血浆中总皮质醇浓度的实验室无需额外设备即可采用该方法。
