Oscai L B, Miller W C
Med Sci Sports Exerc. 1986 Feb;18(1):6-9.
A rat model for severe obesity has been developed by feeding the animals a fat-rich, sugar-rich diet. The concentration of fat in the diet was similar to what most Americans consume (about 40% kcal from fat). Calories from sugar was calculated to be 40.6%. As adults, body fat content in these animals averaged 61 or 51%, depending on whether the fat-rich, sugar-rich diet caused hyperphagia. The rate of body fat accretion in these severely obese rats raised in litters of four was estimated to be 1.78 +/- 0.12 (SE) g X d-1 (61% body fat) or 0.9 +/- 0.03 g X d-1 (51% body fat). In contrast, lean rats eating a diet of Purina chow deposited fat at a rate of 0.20 +/- 0.02 g X d-1, resulting in a carcass fat content of 18%. Preliminary evidence based on adult body weights of sugar-fed rats suggests that sucrose alone can cause severe obesity similar to that seen with dietary fat alone. Currently, an attempt is being made to determine how dietary fat and/or dietary sugar work to produce severe obesity. One possibility is that dietary fat in the form of a chylomicron and dietary sugar in the form of a very low density lipoprotein may modify adipose tissue lipoprotein lipase activity. This enzyme acts as a gatekeeper for circulating triglycerides entering the adipocyte. It is our belief that the results obtained will help to lay the groundwork for determination of the role of exercise in weight control.
通过给动物喂食富含脂肪和糖的饮食，已建立了一种严重肥胖的大鼠模型。饮食中的脂肪浓度与大多数美国人的摄入量相似（约40%的热量来自脂肪）。计算得出糖提供的热量为40.6%。成年后，这些动物的体脂含量平均为61%或51%，这取决于富含脂肪和糖的饮食是否导致食欲亢进。在每窝四只饲养的这些严重肥胖大鼠中，体脂增加率估计为1.78±0.12（标准误）克×天⁻¹（体脂61%）或0.9±0.03克×天⁻¹（体脂51%）。相比之下，食用普瑞纳饲料的瘦大鼠脂肪沉积速率为0.20±0.02克×天⁻¹，导致胴体脂肪含量为18%。基于喂食糖的大鼠成年体重的初步证据表明，仅蔗糖就能导致与仅食用膳食脂肪时相似的严重肥胖。目前，正在尝试确定膳食脂肪和/或膳食糖是如何导致严重肥胖的。一种可能性是，乳糜微粒形式的膳食脂肪和极低密度脂蛋白形式的膳食糖可能会改变脂肪组织脂蛋白脂肪酶的活性。这种酶是循环甘油三酯进入脂肪细胞的守门人。我们相信，所获得的结果将有助于为确定运动在体重控制中的作用奠定基础。
