Reduction in triacylglycerol levels by fish oil correlates with free fatty acid levels in ad libitum fed rats.
Reduction in triacylglycerol levels by fish oil correlates with free fatty acid levels in ad libitum fed rats.
复制标题
鱼油对三酰甘油水平的降低与随意喂养的大鼠中的游离脂肪酸水平相关。
作者：
Otto,DA;Baltzell,JK;Wooten,JT
给大鼠喂食（2或6周）含有猪油（LD）或鲱鱼油（MO）的纯化饮食，其中两种饮食脂肪水平为，低脂（LF）和中脂（MF）饮食中分别占能量的11.5%和20.8%。在饮食期后，在禁食过夜或不间断自由进食后处死大鼠。这些研究旨在研究我们先前报告的MO效应（即血浆游离脂肪酸（FFA）水平降低和肝脏甘油三酯蓄积）对处死时动物膳食脂肪浓度和营养状态的依赖性。在所有条件下，观察到MO喂养的大鼠血浆三酰甘油和胆固醇水平相对于LD喂养的大鼠降低。在两种膳食脂肪浓度下，通过MO喂养，FFA水平持续降低，但仅在从自由采食的大鼠采集血液时。在这些条件下，有一个显着的正相关关系，血浆游离脂肪酸和三酰甘油浓度。血浆FFA水平降低可能是鱼油（FO）降低三酰甘油作用的另一种机制。LF和MF MO饮食引起血浆葡萄糖水平升高，胰岛素浓度无显著变化，表明MO导致FFA减少与胰岛素浓度或胰岛素敏感性变化无关。MO饮食对骨骼肌或附睾脂肪组织脂蛋白脂酶活性没有影响，表明富含三酰甘油的脂蛋白的catenoprotein对MO依赖的血浆三酰甘油和FFA的降低几乎没有贡献（如果有的话）。先前报道的积累肝三酰甘油高脂肪（HF; 30%的能量）MO喂养后，没有观察到LF或MF MO饮食，这表明FO的明显直接抑制三酰甘油分泌施加速率限制，只有当喂食HF饮食。
Rats were fed (for 2 or 6 wk) purified diets containing lard (LD) or menhaden oil (MO) at two levels of dietary fat,i.e., at 11.5 and 20.8% of energy in the low fat (LF) and the medium fat (MF) diets, respectively. Following the diet period, rats were sacrificed after either an overnight fast or after uninterruptedad libitumfeeding. The studies were designed to investigate the dependence of our previously reported effects of MO,i.e.the reduction of plasma free fatty acid (FFA) levels and accumulation of hepatic triacylglycerols, on the dietary fat concentration and the nutritional state of the animal at the time of sacrifice. Reductions in plasma triacylglycerol and cholesterol levels in MO-fed relative to LD-fed rats were observed under all conditions. FFA levels were consistently reduced by MO-feeding at both dietary fat concentrations, but only when blood was sampled fromad libitumfed rats. Under these conditions there was a significant positive relationship between plasma FFA and triacylglycerol concentrations. Reduction in plasma FFA levels may be an additional mechanism associated with the triacylglycerol-lowering effect of fish oil (FO). The LF and MF MO diets caused a rise in plasma glucose levels with no significant change in insulin concentration, indicating that the reduction of FFA by MO was not related to changes in insulin concentration or insulin sensitivity. The MO diets had no effect on skeletal muscle or epididymal adipose tissue lipoprotein lipase activity, demonstrating that catabolism of triacylglycerol-rich lipoproteins contributes little, if any, to the MO-dependent reductions of plasma triacylglycerol and FFA. The previously reported accumulation of hepatic triacylglycerols after high fat (HF; 30% of energy) MO-feeding was not observed with the LF or MF MO diets, suggesting that the apparent direct inhibition of triacylglycerol secretion by FO imposes a rate-limitation only when feeding HF diets.