Fig. 4.

Synthetic rates of fatty acids, sterols, and triglycerides in livers of wild-type and Elovl5^−/− mice. A: In vivo rates of fatty acids and sterol synthesis in liver. Five wild-type mice and five Elovl5^−/− mice were injected intraperitoneally with [³H]H₂O (50 mCi in 0.2 ml of saline). One h after injection, livers were removed and fatty acids and digitonin-precipitable sterols were extracted. Incorporation of ³H into newly synthesized fatty acids and sterols were measured as described in Experimental Procedures. Each bar represents the mean ± SE of the values from five mice. * P < 0.05 using Student's t-test. Similar results were obtained in two additional independent experiments. B: Triglyceride synthesis in primary hepatocytes isolated from WT and Elovl5^−/− mice. Primary hepatocytes were isolated from three WT and three Elovl5^−/− mice and attached on collagen coated dishes for 2 h in duplicate. After the attachment period, the cells were incubated with 1.5 mM [¹⁴C]glycerol for 3 h. Lipids were extracted from the cells and triglycerides were separated by TLC as described in Experimental Procedures. Incorporation of radiolabeled glycerol to triglycerides was measured. Each bar represents the mean ± SE.