Figure 4. Hypertriglyceridemia and delayed clearance of dietary lipids in Sdc1^–/– and Ndst1^f/fAlbCre⁺ mice are not additive traits.

(A) Plasma triglycerides were measured in plasma samples from fasted mice. There was no difference in plasma triglycerides in Sdc1^–/–Ndst1^f/fAlbCre⁺ (triangles, n = 9), Sdc1^–/–Ndst1^f/fAlbCre^– (open circles, n = 7), and Ndst1^f/fAlbCre⁺ (squares, n = 7) mice, although all 3 genotypes were significantly elevated above the wild-type, Ndst1^f/fAlbCre^– (closed circles, n = 13). Horizontal bars indicate mean values. (B) Retinol ester excursions were measured at the times indicated in wild-type (filled circles, n = 3), Sdc1^–/– (open circles, n = 3), Ndst1^f/fAlbCre⁺ (squares, n = 3), and Sdc1^–/–Ndst1^f/fAlbCre⁺(triangles, n = 3) mice. Animals were fasted for 4 hours in the morning and given 200 μl of corn oil containing [³H]retinol by gavage. Blood samples were taken at the indicated times, and radioactivity remaining in 10 μl of serum was determined by scintillation counting. The values are expressed as mean ± SD. The areas under the curves were 4,100 ± 1,200 for wild-type, 8,400 ± 300 for Sdc1^–/–, 8,300 ± 400 for Ndst1^f/fAlbCre⁺, and 6,900 ± 1,000 for Sdc1^–/–Ndst1^f/fAlbCre⁺ mice. Clearance was significantly delayed in the Sdc1^–/– mice compared with wild-type (P = 0.0034), whereas the difference observed between Sdc1^–/– and Sdc1^–/–Ndst1^f/fAlbCre⁺ animals was not significant (P = 0.1373).