Wide L, Bengtsson C, Birgegård G
Department of Clinical Chemistry, University Hospital, Uppsala, Sweden.
Br J Haematol. 1989 May;72(1):85-90. doi: 10.1111/j.1365-2141.1989.tb07657.x.
When a sensitive radioimmunoassay for erythropoietin in serum (S-Epo), using labelled recombinant hEpo and antiserum to urinary hEpo, was evaluated for clinical use, a large intra-individual variation was observed during a 24 h period. The possibility of a circadian rhythm with a variation during day time which has to be considered for clinical evaluation of the S-Epo level was investigated in 27 hospitalized adult patients. They had various illnesses, but all had a level of S-Epo at 08.00 or 12.00 hours within the reference range of healthy individuals and normal cortisol levels during the 24 h. A well-marked circadian rhythm of S-Epo was found with the lowest mean level at 08.00 hours, a 42% increase at 16.00 hours and a 60% increase to the highest at 20.00 hours. Twelve (44%) of the 27 patients, with S-Epo levels within the reference range (3.3-13.5 IU/l) at 08.00 or 12.00 hours, had levels above this range at 16.00 hours. For clinical evaluation of the S-Epo level, the time of day for collection of the blood specimen has to be taken into consideration. It is recommended that blood specimens are taken in the morning between 07.30 and 12.00 hours. The mechanisms behind the observed circadian rhythm of S-Epo are unknown.
当使用标记的重组人促红细胞生成素和抗尿促红细胞生成素抗血清对血清促红细胞生成素（S-Epo）进行灵敏的放射免疫分析以评估其临床应用时，在24小时内观察到个体内存在较大差异。在27例住院成年患者中，研究了S-Epo水平的昼夜节律变化及其在白天的变化情况，这在S-Epo水平的临床评估中必须予以考虑。这些患者患有各种疾病，但在24小时内，他们在08:00或12:00时的S-Epo水平均在健康个体的参考范围内，且皮质醇水平正常。研究发现S-Epo有明显的昼夜节律，08:00时平均水平最低，16:00时升高42%，20:00时升至最高，升高60%。27例患者中有12例（44%）在08:00或12:00时S-Epo水平在参考范围（3.3 - 13.5 IU/l）内，但在16:00时高于此范围。对于S-Epo水平的临床评估，必须考虑采集血样的时间。建议在上午07:30至12:00之间采集血样。观察到的S-Epo昼夜节律背后的机制尚不清楚。
