Touitou Y, Touitou C, Charransol G, Reinberg A, Thomas J, Bogdan A, Barthelemy C, Desgrez P
Int J Chronobiol. 1983;8(3):175-92.
The circadian (circannual for oxalic acid) variations of 13 urinary variables (volume, creatinine, calcium, oxalic acid, glycolic acid, 17-ketosteroids, 17-hydroxycorticosteroids, phosphates, urea, uric acid, chloride, sodium, and potassium) have been documented in 7 calcium oxalate renal stone formers and 7 healthy men (control group). Urine was collected every 4 h over a period of 24 h. All subjects had the same synchronization: diurnal activity from 07(00) to 23(00) +/- 1 h and nocturnal rest; meals were given at fixed clock hours (08(00), 12(30) and 20(00) +/- 1 h). A statistically-significant rhythm (p less than 0.05) was validated for all variables except urea and calcium in healthy men. In renal stone formers, 6 variables (calcium, oxalic acid, and glycolic acid in particular) had no detectable circadian rhythm. However, a periodicity of c. 8 h (ultradian rhythm) was demonstrated for calcium and oxalic acid with peaks being located around 02(00), 10(00), and 18(00). No circannual variations in oxalic acid output could be observed. The present study shows an alteration of the periodicity of calcium and oxalic metabolisms, i.e. the loss of a circadian (24-h) rhythm and the occurrence of an ultradian rhythm of 8 h. The risk of calcium-oxalate crystallisation appears thus greater at 02(00), 10(00), and 18(00). Furthermore, any study dealing with oxalic acid excretion should state the season of urine collection when comparing renal stone formers and healthy subjects, as significant differences in oxaluria may appear during the summer months and not during the rest of the year.
已记录了7名草酸钙肾结石患者和7名健康男性（对照组）13种尿液变量（尿量、肌酐、钙、草酸、乙醇酸、17 - 酮类固醇、17 - 羟皮质类固醇、磷酸盐、尿素、尿酸、氯、钠和钾）的昼夜（草酸为年周期）变化。在24小时内每4小时收集一次尿液。所有受试者作息同步：白天活动时间为07(00)至23(00) ± 1小时，夜间休息；三餐在固定时间（08(00)、12(30)和20(00) ± 1小时）供应。除健康男性的尿素和钙外，所有变量均验证有统计学意义的节律（p < 0.05）。在肾结石患者中，6种变量（特别是钙、草酸和乙醇酸）未检测到昼夜节律。然而，钙和草酸表现出约8小时的周期性（超日节律），峰值出现在02(00)、10(00)和18(00)左右。未观察到草酸排出量的年周期变化。本研究表明钙和草酸代谢的周期性发生改变，即昼夜（24小时）节律丧失，出现8小时的超日节律。因此，在02(00)、(10)00)和18(00)时草酸钙结晶的风险似乎更大。此外，在比较肾结石患者和健康受试者时，任何涉及草酸排泄的研究都应说明尿液收集的季节，因为夏季草酸尿可能出现显著差异，而一年中的其他时间则不会。
