Bar-On H, Roheim P S, Eder H A
J Clin Invest. 1976 Mar;57(3):714-21. doi: 10.1172/JCI108329.
The lipoproteins of rats fed a high sucrose diet and made diabetic by administration of 45 mg/kg of streptozotocin were studied. All lipoprotein classes were found to be present in increased concentrations. The apolipoprotein composition of the various lipoprotein fractions was studied by polyacrylamide-gel electrophoresis in the presence of 8 M urea, isoelectric focusing in the presence of 8 M urea, and sodium dodecyl sulfate gel electrophoresis in polyacrylamide gels. In the very low density lipoproteins (VLDL) of diabetic rats, there was a marked alteration in the relative amounts of C proteins by polyacrylamide-gel electrophoresis, and this was found by isoelectric focusing to be primarily a relative increase in C-III-3 apoprotein and a decrease in C-III-O. In addition, in the diabetic rats, the VLDL contained a protein of mol wt 46,000, the A-IV protein, which normally is only present in the high density lipoproteins. In the high density lipoproteins, (HDL) the same alterations in pattern of the C proteins seen in the VLDL were present. Furthermore, the arginine-rich and A-IV protein normally present in HDL could not be detected in the HDL, although the other apolipoproteins are present. Apolipoprotein concentrations were determined by quantitative immunoelectrophoresis. It was found that in the diabetic rats there was an increase in the total amount of apo-B in the plasma, with the increment divided proportionately between the VLDL and the low density lipoprotein (LDL). The total apo-C concentration of plasma increased minimally. The A-IV concentration of plasma increased by 27%; it decreased markedly in the HDL, but appeared in increased amounts in both VLDL and in the d greater than 1.21 fraction. The arginine-rich protein decreased by 63% in the plasma and decreased significantly in the HDL, but increased in VLDL, LDL, and in the d greater than 1.21 fraction. These alterations in apolipoprotein patterns in diabetic animals suggest that the apolipoproteins may play an important role in determining the concentration of various lipoprotein fractions, or may be the result of altered metabolism of the lipoproteins. These lipoproteins with altered apolipoprotein composition may have important biologic differences from normal lipoporteins. Nevertheless, the HDL, despite the fact that it is deficient in some of its major constituents, was unchanged in its cholesterol content.
对喂食高蔗糖饮食并通过注射45毫克/千克链脲佐菌素诱导糖尿病的大鼠的脂蛋白进行了研究。发现所有脂蛋白类别的浓度均升高。通过在8M尿素存在下的聚丙烯酰胺凝胶电泳、在8M尿素存在下的等电聚焦以及聚丙烯酰胺凝胶中的十二烷基硫酸钠凝胶电泳，研究了各种脂蛋白组分的载脂蛋白组成。在糖尿病大鼠的极低密度脂蛋白（VLDL）中，通过聚丙烯酰胺凝胶电泳发现C蛋白的相对含量有明显改变，通过等电聚焦发现这主要是C-III-3载脂蛋白相对增加以及C-III-O减少。此外，在糖尿病大鼠中，VLDL含有一种分子量为46,000的蛋白质，即A-IV蛋白，该蛋白通常仅存在于高密度脂蛋白中。在高密度脂蛋白（HDL）中，观察到与VLDL中C蛋白模式相同的改变。此外，尽管存在其他载脂蛋白，但通常存在于HDL中的富含精氨酸蛋白和A-IV蛋白在HDL中无法检测到。通过定量免疫电泳测定载脂蛋白浓度。发现糖尿病大鼠血浆中载脂蛋白B的总量增加，增加量在VLDL和低密度脂蛋白（LDL）之间按比例分配。血浆中载脂蛋白C的总浓度略有增加。血浆中A-IV浓度增加了27%；它在HDL中显著降低，但在VLDL和密度大于1.21的组分中含量增加。糖尿病动物中载脂蛋白模式的这些改变表明，载脂蛋白可能在决定各种脂蛋白组分的浓度方面起重要作用，或者可能是脂蛋白代谢改变的结果。这些载脂蛋白组成改变的脂蛋白可能与正常脂蛋白具有重要的生物学差异。然而，HDL尽管其一些主要成分缺乏，但其胆固醇含量未变。
