Lacombe C, Corraze G
UA 644 CNRS, Institut de Physiologie, Université Paul Sabatier, Toulouse, France.
J Nutr. 1989 Oct;119(10):1513-8. doi: 10.1093/jn/119.10.1513.
This study was designed to define the effect of dietary restriction and cholesterol feeding on disturbances of very low density lipoprotein (VLDL) catabolism. Three groups of 15 New Zealand rabbits were fed standard or cholesterol-rich diets either ad libitum or in restricted amounts and in vitro binding assays on hepatocyte membranes were carried out after 4, 8, 12 and 20 d. Cholesterol feeding reduced the specific binding of labeled beta-VLDL to liver membranes. Dietary restriction, which enhances the hypercholesterolemia induced by cholesterol feeding, had no additional effect on the down-regulation of beta-VLDL specific binding. In another set of experiments the uptake of labeled beta-VLDL by various tissues was measured after 15 d of feeding the diets. Cholesterol feeding decreased uptake of these lipoproteins by the liver and various extrahepatic tissues, such as skin, intestine, muscle, adipose tissue, kidneys, spleen and aorta. Additional changes occurred in liver and intestine with dietary restriction. In liver beta-VLDL uptake in the group fed a restricted amount of the cholesterol-containing diet was 70% of that in the group fed the same diet ad libitum. Taken together, the results suggest that dietary restriction acts mainly on the receptor-independent catabolism of beta-VLDL.
本研究旨在确定饮食限制和胆固醇喂养对极低密度脂蛋白（VLDL）分解代谢紊乱的影响。将三组15只新西兰兔分别随意或限量喂食标准饮食或富含胆固醇的饮食，并在4、8、12和20天后对肝细胞膜进行体外结合试验。胆固醇喂养降低了标记的β-VLDL与肝细胞膜的特异性结合。饮食限制会加剧胆固醇喂养诱导的高胆固醇血症，但对β-VLDL特异性结合的下调没有额外影响。在另一组实验中，喂食15天后测量了各种组织对标记的β-VLDL的摄取。胆固醇喂养减少了肝脏和各种肝外组织（如皮肤、肠道、肌肉、脂肪组织、肾脏、脾脏和主动脉）对这些脂蛋白的摄取。饮食限制使肝脏和肠道发生了其他变化。在喂食限量含胆固醇饮食的组中，肝脏对β-VLDL的摄取量是随意喂食相同饮食组的70%。综上所述，结果表明饮食限制主要作用于β-VLDL的非受体依赖性分解代谢。
