Figure 4.

Heparin, but not RAP, competes for DiI-apoE-VLDL uptake by adipocytes. Differentiated adipocytes were cultured on glass coverslips and incubated with DiI-labeled apoE-VLDL (4 μg/ml) in the presence or absence (upper panel) of either heparin (500 μg/ml, middle panel) or RAP-GST (50 μg/ml, lower panel) at 37°C for 3 h. Cells were then fixed and processed for fluorescence microscopy. Left panels, phase contrast image; right panels, rhodamine filter set (550 nm excitation-573 nm emission). Magnification, 630×.