Marshall J F, Apostolopoulos J J, Brack C M, Howlett G J
Russell Grimwade School of Biochemistry, University of Melbourne, Parkville, Australia.
Biochim Biophys Acta. 1990 Feb 23;1042(3):271-9. doi: 10.1016/0005-2760(90)90153-o.
Hepatic and intestinal RNA levels were measured in rats made nephrotic by injection of puromycin aminonucleoside (PAN). The following increases in hepatic RNA levels, relative to controls, were measured: poly A+ (1.2), ribosomal (1.2), mRNA levels for transferrin (1.8), albumin (3.8) apolipoprotein (apo)E (2.3), apoB (2.5), apoA-II (1.9) and apoA-I (6.1). Increases of 1.5- to 2.2-fold in hepatic mRNA levels for albumin, apoA-II, apoB and apoE were measured in pre-nephrotic animals killed before the onset of proteinuria. Intestinal RNA levels in pre-nephrotic and nephrotic animals were not significantly different from control values. Transcription of the hepatic apoA-I gene increased 1.8-fold in nephrotic animals compared to controls. Immunological detection of apolipoproteins in high-density lipoproteins (HDL) separated by gradient gel electrophoresis indicated an increase in apoA-I and a decrease in apoA-IV and apoE containing HDL particles in nephrosis. To simulate the effects of increased apoA-I gene expression, human apoA-I was added to rat plasma in vivo and in vitro. ApoE was displaced from HDL by increased concentration of apoA-I. The results indicate that relatively small changes in apoA-I levels in the serum lead to significant changes in the apolipoprotein composition of HDL.
通过注射嘌呤霉素氨基核苷（PAN）使大鼠产生肾病，然后测定其肝脏和肠道的RNA水平。相对于对照组，测得肝脏RNA水平有以下升高：多聚腺苷酸（poly A+）升高1.2倍，核糖体RNA升高1.2倍，转铁蛋白的mRNA水平升高1.8倍，白蛋白升高3.8倍，载脂蛋白（apo）E升高2.3倍，apoB升高2.5倍，apoA-II升高1.9倍，apoA-I升高6.1倍。在蛋白尿出现前处死的肾病前期动物中，测得白蛋白、apoA-II、apoB和apoE的肝脏mRNA水平升高了1.5至2.2倍。肾病前期和肾病动物的肠道RNA水平与对照值无显著差异。与对照组相比，肾病动物肝脏apoA-I基因的转录增加了1.8倍。通过梯度凝胶电泳分离的高密度脂蛋白（HDL）中载脂蛋白的免疫检测表明，肾病时含apoA-I的HDL颗粒增加，含apoA-IV和apoE的HDL颗粒减少。为了模拟apoA-I基因表达增加的影响，在体内和体外将人apoA-I添加到大鼠血浆中。apoA-I浓度的增加使apoE从HDL中被置换出来。结果表明，血清中apoA-I水平相对较小的变化会导致HDL载脂蛋白组成发生显著变化。
