Kamali F, Edwards C, Wood P, Wynne H A, Kesteven P
Wolfson Unit of Clinical Pharmacology, University of Newcastle, Newcastle upon Tyne, United Kingdom.
Am J Hematol. 2001 Nov;68(3):159-63. doi: 10.1002/ajh.1172.
There is no information available on temporal variability in plasma vitamin K concentrations and its relationship to coagulation processes. We investigated the possible existence of temporal changes in plasma vitamin K and lipid concentrations and activity of clotting factors II, VII, IX, and X and relationships between these variables. Plasma vitamin K and lipid concentrations and clotting factor activity were measured at four-hour intervals for 28 hours in a group of healthy volunteers. Temporal variations existed in plasma vitamin K concentrations, with a mean maximum at 22:00 hr and a mean minimum (32% of the maximum) at 10:00 hr. Plasma triglycerol concentrations mirrored the changes in vitamin K concentrations. Mean factor VII activity was positively correlated with mean total plasma cholesterol concentrations (r = 0.714; P < 0.0001) and with mean plasma low density lipoprotein (LDL) cholesterol concentrations (r = 0.461; P < 0.0001). No distinct correlations were found between plasma vitamin K concentrations and either high density lipoprotein (HDL) or LDL cholesterol concentrations, or between triglycerol, HDL, or LDL cholesterol concentrations and functional activity of factors II, IX, and X. Plasma vitamin K concentrations did not correlate with the functional activity of any of the clotting factors. The presence of a correlation between plasma cholesterol concentrations and factor VII activity for blood samples collected at four-hour intervals suggests that plasma cholesterol concentrations may have a more acute effect on factor VII activity. Temporal variations in plasma vitamin K concentrations indicate that a single time point measurement may be an inappropriate method of establishing vitamin K status in an individual.
目前尚无关于血浆维生素K浓度的时间变异性及其与凝血过程关系的信息。我们研究了血浆维生素K和脂质浓度以及凝血因子II、VII、IX和X的活性是否存在时间变化，以及这些变量之间的关系。在一组健康志愿者中，每隔4小时测量一次血浆维生素K和脂质浓度以及凝血因子活性，持续28小时。血浆维生素K浓度存在时间变化，平均最大值出现在22:00，平均最小值（为最大值的32%）出现在10:00。血浆甘油三酯浓度反映了维生素K浓度的变化。平均因子VII活性与平均总血浆胆固醇浓度呈正相关（r = 0.714；P < 0.0001），与平均血浆低密度脂蛋白（LDL）胆固醇浓度呈正相关（r = 0.461；P < 0.0001）。未发现血浆维生素K浓度与高密度脂蛋白（HDL）或LDL胆固醇浓度之间存在明显相关性，也未发现甘油三酯、HDL或LDL胆固醇浓度与因子II、IX和X的功能活性之间存在明显相关性。血浆维生素K浓度与任何凝血因子的功能活性均无相关性。每隔4小时采集的血样中血浆胆固醇浓度与因子VII活性之间存在相关性，这表明血浆胆固醇浓度可能对因子VII活性有更急性的影响。血浆维生素K浓度的时间变化表明，单一时间点测量可能不是确定个体维生素K状态的合适方法。
