title: Experimental nephrotic syndrome in the rat induced by puromycin aminonucleoside: hepatic synthesis of lipoproteins and apolipoproteins.
abstract: Hepatic synthesis of lipoproteins and apolipoproteins was investigated in male Wistar rats with severe nephrotic syndrome induced by puromycin aminonucleoside by incubating liver slices with a mixture of 14C-amino acids. Labeled lipoproteins were separated by preparative ultracentrifugation from the incubation medium after the addition of carrier plasma. The incorporation of 14C-amino acids into very low density lipoproteins (VLDL) (1.006 g/ml), low density lipoproteins (LDL) (1.006-1.063 g/ml) and high density lipoproteins (HDL) (1.063-1.210 g/ml) was increased in nephrotic liver 6.1-, 5.7- and 5.0-fold, respectively. The measurement of radioactivity associated to apolipoproteins isolated by SDS-PAGE documented an increased incorporation into apolipoprotein E (apoE) of nephrotic VLDL (33.1% vs 20% of the total radioactivity incorporated into VLDL apoproteins) and a markedly increased incorporation into apolipoprotein A-I (apo-A-I) of nephrotic HDL (44.3% vs 16.3% of the total radioactivity incorporated into HDL apoproteins). In nephrotic liver, the total incorporation of amino acids into apolipoproteins (apoVLDL + apoLDL + apoHDL) was increased 12.6 times for apo-A-I, 6,4 times for apoB, 5.0 times for apoE, 4.2 times for apoC + apoA-II and 2.5 times for apoA-IV. We suggest that, in nephrotic liver: (a) the synthesis of VLDL, LDL and HDL is increased, and (b) the total synthesis of apoA-I is selectively increased when compared to that of the other apolipoproteins.
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D000818:Animals; D001053:Apolipoproteins / Q000096:biosynthesis*; D008074:Lipoproteins / Q000096:biosynthesis*; D008099:Liver / Q000503:physiopathology*; D008297:Male; D009404:Nephrotic Syndrome / Q000139:chemically induced / Q000503:physiopathology*; D011692:Puromycin Aminonucleoside; D051381:Rats
chemical_list: D000596:Amino Acids; D001053:Apolipoproteins; D008074:Lipoproteins; D011692:Puromycin Aminonucleoside