Haskell M J, Mazumder R N, Peerson J M, Jones A D, Wahed M A, Mahalanabis D, Brown K H
Program in International Nutrition, Department of Nutrition, University of California, Davis, USA.
Am J Clin Nutr. 1999 Nov;70(5):874-80. doi: 10.1093/ajcn/70.5.874.
The deuterated-retinol-dilution (DRD) technique provides a quantitative estimate of total body stores of vitamin A. However, it is not known whether the technique can detect changes in vitamin A pool size in response to different intakes of vitamin A.
Our objective was to determine the responsiveness of the DRD technique to 3 different daily supplemental vitamin A intakes during a period of 2.5-4 mo.
Two oral doses of [(2)H(4)]retinyl acetate [52.4 micromol retinol equivalent (RE)] were administered on study days 1 and 91 to 26 men (18-32 y of age) who were consuming controlled, low-vitamin A diets, and receiving daily either 0, 5.2, or 10.5 micromol RE of unlabeled supplemental retinyl palmitate during a 75- or 129-d period. Plasma isotopic ratios of [(2)H(4)]retinol to retinol on day 115 were used to estimate final vitamin A body stores per Furr et al (Am J Clin Nutr 1989;49:713-6).
Final ( +/- SD) estimated vitamin A pool sizes were 0.048 +/- 0.031, 0.252 +/- 0.045, and 0.489 +/- 0.066 mmol in the treatment groups receiving 0, 5.2, and 10.5 micromol RE/d, respectively (P < 0.001). Estimated mean changes in vitamin A pool sizes were similar to those expected for the vitamin A-supplemented groups [estimated:expected (95% CI of change in pool size): 1.08 (0.8, 1.2) and 1.17 (1.0, 1.3)].
The DRD technique can detect changes in total body stores of vitamin A in response to different daily vitamin A supplements. However, abrupt changes in dietary vitamin A intake can affect estimates of total-body vitamin A stores.
氘代视黄醇稀释（DRD）技术可对维生素A的全身储存量进行定量评估。然而，该技术能否检测出因不同维生素A摄入量而导致的维生素A储备池大小的变化尚不清楚。
我们的目的是确定在2.5至4个月期间，DRD技术对3种不同的每日维生素A补充摄入量的反应性。
在研究的第1天和第91天，给26名年龄在18至32岁、食用受控低维生素A饮食且在75或129天期间每天分别接受0、5.2或10.5微摩尔视黄醇当量（RE）未标记补充视黄醇棕榈酸酯的男性口服两剂[（2）H（4）]视黄醇乙酸酯[52.4微摩尔视黄醇当量（RE）]。根据Furr等人（《美国临床营养学杂志》1989年；49：713 - 6）的方法，使用第115天血浆中[（2）H（4）]视黄醇与视黄醇的同位素比率来估计最终的维生素A身体储备量。
在分别接受0、5.2和10.5微摩尔RE/天的治疗组中，最终（±标准差）估计的维生素A储备池大小分别为0.048±0.031、0.252±0.045和0.489±0.066毫摩尔（P<0.001）。维生素A储备池大小的估计平均变化与维生素A补充组预期的变化相似[估计：预期（储备池大小变化的95%置信区间）：1.08（0.8，1.2）和1.17（1.0，1.3）]。
DRD技术能够检测出因不同的每日维生素A补充剂而导致的维生素A全身储备量的变化。然而，饮食中维生素A摄入量的突然变化会影响全身维生素A储备量的估计。
