Schuster G S, Erbland J F, Wyrick S D, Singh B B
J Oral Pathol. 1986 Sep;15(8):430-3. doi: 10.1111/j.1600-0714.1986.tb00652.x.
The current study examines the effects of N-nitrosonornicotine (NNN) and all trans-retinoic acid (RA) on the synthesis and composition of lipids of oral epithelial cells grown in culture. Cells were exposed to NNN, RA or methylene chloride (the vehicle for the NNN and RA) and the lipids labelled with [14C]-acetate. Lipids were extracted from the cells, separated by paper chromatography, located by autoradiography, and acetate incorporation determined by liquid scintillation spectrometry. Cholesterol labelling was significantly decreased by the RA between 4 and 48 h when compared to the NNN-treated or control cells. After 48 h the incorporation levels in the presence of the two last compounds decreased. Free fatty acid labelling was also significantly less in cells exposed to RA, while labelling of triglycerides and phospholipids was increased. N-nitrosonornicotine seemed to produce a decreased labelling of cholesterol after 96 h continuous exposure. The results of these studies suggest that retinoid rapidly elevates the cell content of lipid formed from the glycerolipid pathway and membrane mechanisms may be modulated by this effect.
本研究考察了N-亚硝基降烟碱（NNN）和全反式维甲酸（RA）对培养的口腔上皮细胞脂质合成及组成的影响。将细胞暴露于NNN、RA或二氯甲烷（NNN和RA的溶剂）中，并用[¹⁴C]-乙酸盐标记脂质。从细胞中提取脂质，通过纸色谱法分离，放射自显影定位，并用液体闪烁光谱法测定乙酸盐掺入量。与NNN处理组或对照组细胞相比，RA在4至48小时内显著降低了胆固醇标记。48小时后，后两种化合物存在时的掺入水平降低。暴露于RA的细胞中游离脂肪酸标记也显著减少，而甘油三酯和磷脂的标记增加。连续暴露96小时后，N-亚硝基降烟碱似乎使胆固醇标记减少。这些研究结果表明，类视黄醇能迅速提高由甘油脂质途径形成的细胞脂质含量，且这种作用可能会调节膜机制。
