Faculty of Health Science, University of Copenhagen, Copenhagen, Denmark.
Endocrine. 2012 Oct;42(2):430-5. doi: 10.1007/s12020-012-9641-z. Epub 2012 Mar 6.
We wanted to evaluate the cutaneous synthesis of 25OHD and cholecalciferol after one whole-body exposure to ultraviolet radiation type B (UVB) in a randomized setup. Healthy volunteers were randomized to one whole-body exposure in a commercial tanning bed with UVB emission (UVB/UVA ratio 1.8-2.0%) or an identical placebo tanning bed without UVB. The output in the 280-320 nm range was 450 µW/cm². Blood samples were analyzed for 25OHD and cholecalciferol at baseline and during 7 days after treatment. We included 20 volunteers, 11 to UVB and 9 to placebo treatment. During the first 6 h, no significant differences in 25OHD between the groups were found. At the end of the study, we found a mean increase of 25OHD in the UVB group of 4.5 nmol/l (SD 7 nmol/l) compared to a decline of -1.2 nmol/l (SD 7 nmol/l) in the placebo group (p = 0.1). A linear mixed model yielded an increase of 25OHD in the UVB group of 1.0 nmol/l per 24 h (p < 0.01). For cholecalciferol, we found a near significant increase of 1 pmol/l per hour in the UVB group compared to the placebo group during the first 6 h (p = 0.052). One tanning bed session had significant, but modest impact on the level of 25OHD during 7 days after exposure to UVB.
我们旨在评估在接受全身紫外线 B（UVB）辐射的随机条件下，25OHD 和胆钙化醇的皮肤合成情况。将健康志愿者随机分配至接受商业紫外线晒黑床（UVB/UVA 比值为 1.8-2.0%）或相同的无 UVB 安慰剂紫外线晒黑床的全身照射。280-320nm 范围内的输出量为 450µW/cm²。在基线和治疗后 7 天内采集血液样本，以分析 25OHD 和胆钙化醇。我们纳入了 20 名志愿者，11 名接受 UVB 治疗，9 名接受安慰剂治疗。在最初的 6 小时内，两组之间的 25OHD 无显著差异。在研究结束时，我们发现 UVB 组的 25OHD 平均增加了 4.5nmol/l（SD 7nmol/l），而安慰剂组则下降了-1.2nmol/l（SD 7nmol/l）（p=0.1）。线性混合模型显示，UVB 组的 25OHD 每 24 小时增加 1.0nmol/l（p<0.01）。对于胆钙化醇，我们发现，在最初的 6 小时内，UVB 组每小时增加 1pmol/l，与安慰剂组相比接近显著（p=0.052）。单次晒黑床照射对 UVB 暴露后 7 天内 25OHD 水平有显著但适度的影响。
