Fig. 2.

Effect of IL-6 on secretion of apoB in various lipoprotein density fractions. A: effect of IL-6 (0.5 nM) or insulin (100 nM) on the secretion of very low density lipoprotein (VLDL) apoB (density <1.019 g/ml) and infranatant apoB-containing lipoproteins (density >1.019 g/ml). VLDL was isolated by ultracentrifugation of pooled media, and VLDL and infranatant fractions were assayed for apoB content by RIA. Results are averages ± SD of 4 pools derived from 5 plates each from 2 independent rat liver experiments. *Means differ from basal conditions (B) compared with IL-6 or insulin (INS) conditions at a probability level of at least P < 0.05. B: effect of IL-6 on secretory ¹⁴C-labeled apolipoproteins derived from isolated VLDL (density <1.019 g/ml), low density lipoprotein (LDL) (1.019 g/ml < density <1.063 g/ml), and high density lipoprotein (HDL) (1.063 g/ml < density <1.225 g/ml) following separation by SDS-PAGE and visualization using the phosphorimager. ¹⁴C molecular weight (MW) markers (center lane) are shown with corresponding molecular masses (kDa).