Stich H F, Hornby A P, Dunn B P
Cancer Lett. 1986 Feb;30(2):133-41. doi: 10.1016/0304-3835(86)90081-9.
Beta-carotene levels of exfoliated oral mucosa cells can be increased severalfold by the oral administration of this provitamin. Beta-carotene was estimated by HPLC analysis in pronase-treated exfoliated cells obtained by brushing the entire oral mucosa with a toothbrush. A small percentage of individuals did not respond with an increase of beta-carotene in their mucosa cell in spite of a relatively large intake of the provitamin (360 mg in 4 days, or 2880 mg in 16 weeks, respectively). Levels of beta-carotene in the mucosa cells are affected by the concurrent administration of vitamin A: 0.27 ng beta-carotene per 10(6) cells in the placebo group, 1.79 ng following the intake of beta-carotene (180 mg/week for 16 weeks), and 4.29 ng after beta-carotene (180 mg/week for 16 weeks) plus vitamin A (100,000 IU/week for 16 weeks) consumption. The considerable variations in tissue levels of beta-carotene following its oral administration must be taken into account when cancer intervention trials using this agent are designed and evaluated.
通过口服这种维生素原，脱落口腔黏膜细胞中的β-胡萝卜素水平可提高数倍。用牙刷刷整个口腔黏膜获取经链霉蛋白酶处理的脱落细胞，通过高效液相色谱分析来估算β-胡萝卜素含量。尽管维生素原摄入量相对较大（分别为4天内摄入360毫克或16周内摄入2880毫克），仍有一小部分个体的黏膜细胞中β-胡萝卜素含量未增加。黏膜细胞中β-胡萝卜素水平受同时服用维生素A的影响：安慰剂组每10⁶个细胞中β-胡萝卜素含量为0.27纳克，摄入β-胡萝卜素（16周内每周180毫克）后为1.79纳克，摄入β-胡萝卜素（16周内每周180毫克）加维生素A（16周内每周100,000国际单位）后为4.29纳克。在设计和评估使用该试剂的癌症干预试验时，必须考虑口服β-胡萝卜素后组织中β-胡萝卜素水平的显著差异。
