Bernal R, Hutson D G, Dombro R S, Livingstone A, Levi J U, Zeppa R
Metabolism. 1982 Jun;31(6):533-7. doi: 10.1016/0026-0495(82)90090-7.
Insulin acts as a regulator of lipid metabolism by inhibiting the rate of lipolysis. Hyperinsulinemia, produced by the peripheral infusion of glucose, therefore, causes a lowering of plasma free fatty acids (FFA) by decreasing the mobilization of fats from peripheral deposits. Based on previous studies, it was postulated that a lowering of plasma FFA could be produced, in the absence of hyperinsulinemia, by the infusion of glucose directly into the liver. This study was undertaken to investigate the existence of endogenous factors other than insulin, which inhibit lipolysis. It was determined that glucose at a dosage of 0.125 gm/kg/hr could be infused into the portal vein of dogs without increasing plasma insulin levels. This dosage significantly lowered plasma FFA levels when injected into the portal vein but had no effect on plasma FFA when infused peripherally. There were significant decreases in FFA turnover following portal glucose administration, with no changes in fractional turnover. This indicated that the lowered plasma FFA concentrations found following portal infusions of glucose, were due to reduced lipid mobilization from adipose tissue, rather than increased tissue uptake of FFA. These results suggested the existence of an hepatic factor, stimulated by portal glucose infusion, which lowered FFA mobilization from adipose tissue.
胰岛素通过抑制脂肪分解速率来调节脂质代谢。因此，外周输注葡萄糖所产生的高胰岛素血症，通过减少外周脂肪沉积中脂肪的动员，导致血浆游离脂肪酸（FFA）水平降低。基于先前的研究，有人推测在没有高胰岛素血症的情况下，通过直接向肝脏输注葡萄糖也可使血浆FFA水平降低。本研究旨在探究除胰岛素外，抑制脂肪分解的内源性因素的存在情况。研究确定，以0.125克/千克/小时的剂量向犬门静脉输注葡萄糖，不会升高血浆胰岛素水平。该剂量注入门静脉时可显著降低血浆FFA水平，但外周输注时对血浆FFA无影响。门静脉注射葡萄糖后，FFA周转率显著降低，而分数周转率无变化。这表明门静脉输注葡萄糖后血浆FFA浓度降低，是由于脂肪组织中脂质动员减少，而非组织对FFA摄取增加所致。这些结果提示存在一种由门静脉葡萄糖输注刺激产生的肝脏因子，它可降低脂肪组织中FFA的动员。
