Chambaz J, Guillouzo A, Cardot P, Pepin D, Bereziat G
Biochim Biophys Acta. 1986 Oct 3;878(3):310-9. doi: 10.1016/0005-2760(86)90238-9.
Primary cultures of adult rat hepatocytes were used to compare the uptake and esterification of essential polyunsaturated fatty acids (18:2, 20:3 and 20:4 of the n-6 series) with those of palmitic and oleic acids. The uptake of unesterified fatty acids was linearly related to the free fatty acid/albumin molar ratio for 14 h and did not depend on the unbound free fatty acid level. Whatever the initial free fatty acid/albumin molar ratio, it dropped to 0.5 +/- 0.1 mM after 14 h, thus showing that hepatocytes have a high capacity for clearing free fatty acids from the medium at high free fatty acid/albumin molar ratios. The free fatty acid uptake become saturable when the free fatty acid and albumin concentrations were raised and the free fatty acid/albumin ratio remained constant. This strongly suggests that albumin-hepatocyte interaction mediates free fatty acid uptake. This uptake was identical whatever the fatty acid tested and did not depend on the relative amounts of fatty acids when they were added simultaneously. Triacylglycerol accumulation and synthesis, monitored by labelled fatty acids, were related to the free fatty acid/albumin molar ratio and exhibited no specificity for the series of fatty acids tested. Triacylglycerols were enriched in all the fatty acids tested by up to 60%, and fatty acid incorporation into diacylglycerols and triacylglycerols reflected the free fatty acid composition of the medium. By contrast, neither the level nor the synthesis of phospholipids varied with free fatty acid/albumin, but the rate of phospholipid turnover depended on the fatty acids tested. Accumulation of these acids was smaller in phospholipids than in triacylglycerols. When linoleic and arachidonic acids were added together, phospholipids (especially phosphatidylethanolamine and phosphatidylinositol) were more enriched in arachidonic acid than triacylglycerols. This might be due to the specificity for fatty acid of the enzymes involved in phospholipid metabolism.
成年大鼠肝细胞的原代培养物用于比较必需多不饱和脂肪酸（n-6系列的18:2、20:3和20:4）与棕榈酸和油酸的摄取及酯化情况。未酯化脂肪酸的摄取在14小时内与游离脂肪酸/白蛋白摩尔比呈线性关系，且不依赖于未结合的游离脂肪酸水平。无论初始游离脂肪酸/白蛋白摩尔比如何，14小时后其会降至0.5±0.1 mM，这表明肝细胞在高游离脂肪酸/白蛋白摩尔比时具有从培养基中清除游离脂肪酸的高能力。当游离脂肪酸和白蛋白浓度升高且游离脂肪酸/白蛋白比值保持恒定时，游离脂肪酸摄取变得饱和。这强烈表明白蛋白-肝细胞相互作用介导游离脂肪酸摄取。无论测试何种脂肪酸，这种摄取都是相同的，并且当同时添加脂肪酸时，不依赖于脂肪酸的相对量。通过标记脂肪酸监测的三酰甘油积累和合成与游离脂肪酸/白蛋白摩尔比相关，且对测试的脂肪酸系列无特异性。所有测试的脂肪酸在三酰甘油中的富集高达60%，并且脂肪酸掺入二酰甘油和三酰甘油反映了培养基中的游离脂肪酸组成。相比之下，磷脂的水平和合成均不随游离脂肪酸/白蛋白而变化，但磷脂周转速率取决于测试的脂肪酸。这些酸在磷脂中的积累比在三酰甘油中的小。当亚油酸和花生四烯酸一起添加时，磷脂（尤其是磷脂酰乙醇胺和磷脂酰肌醇）比三酰甘油更富含花生四烯酸。这可能是由于参与磷脂代谢的酶对脂肪酸具有特异性。
