FIGURE 3.

Retinyl ester analyses following treatment of cell cultures with 10 μm all-trans-retinol. Following treatment with 10 μm all-trans-retinol, cell homogenates were processed as described under “Materials and Methods.” The HPLCs shown are representative of triplicate experiments wherein each experiment involved 1 plate with 1 million cells. HPLCs of treated cells are depicted in solid black lines, and those of untreated cell lines are shown as dashed lines. A shows ARPE19; B shows NIH3T3; C shows NIH3T3/L, and D shows NIH3T3/RL cell chromatograms. Retinyl esters with elution times ranging from 10 to 20 min were detected only in NIH3T3/L and NIH3T3/RL cell homogenates. Insets show TLCs of triglycerides in lipid droplets isolated from untreated cells and cells treated with all-trans-retinol. The results demonstrate that the lipid droplet composition differs in the LRAT-expressing cell lines and that all-trans-retinol induces triglyceride formation in ARPE19 and NIH3T3 cell lines.