Bernert J T, Bell C J, Guntupalli J, Hannon W H
Division of Environmental Health Laboratory Sciences, Centers for Disease Control, Atlanta, GA 30333.
Clin Chem. 1988 Jun;34(6):1011-7.
We assessed the clearance of endogenous pseudouridine in humans to evaluate the potential use of this modified nucleoside as a marker of glomerular filtration rate. Pseudouridine concentrations in serum ultrafiltrates and in the corresponding 24-h urine specimens from 19 healthy men were determined by high-performance liquid chromatography. Mean (and SD) pseudouridine concentrations in serum and urine from this group averaged 2.77 (0.34) mumol/L and 203.2 (64.8) mumol/L, respectively. The calculated clearances of the nucleoside [87.3 (24.9) mL/min, n = 19], however, averaged approximately one-third lower than the corresponding creatinine clearances in the same individuals [131.8 (28.4) mL/min]. Measurement of simultaneous clearances of [3H]pseudouridine and [14C]inulin in rats also yielded a lower pseudouridine clearance, 0.78 relative to inulin. Our results are thus consistent with a partial net reabsorption of pseudouridine in both experimental animals and in humans, indicating that this compound would not be a suitable endogenous marker for routine estimation of the glomerular filtration rate.
我们评估了人体内内源性假尿苷的清除率，以评估这种修饰核苷作为肾小球滤过率标志物的潜在用途。通过高效液相色谱法测定了19名健康男性血清超滤液和相应24小时尿液样本中的假尿苷浓度。该组血清和尿液中假尿苷的平均（及标准差）浓度分别为2.77（0.34）μmol/L和203.2（64.8）μmol/L。然而，计算得到的核苷清除率[87.3（24.9）mL/min，n = 19]平均比同一受试者相应的肌酐清除率[131.8（28.4）mL/min]低约三分之一。在大鼠中同时测量[3H]假尿苷和[14C]菊粉的清除率，也得到较低的假尿苷清除率，相对于菊粉为0.78。因此，我们的结果与实验动物和人类中假尿苷的部分净重吸收一致，表明该化合物不是常规估算肾小球滤过率的合适内源性标志物。
