Figure 2. Impaired chylomicron clearance in Ces1/Es-x^−/− mice.

(A) Fat tolerance test in 12-h fasted mice. Mice were gavaged with 150 µl olive oil. Blood samples were collected at the indicated times, plasma was prepared and TG concentrations were measured by gas chromatography. N = 4–6 mice/group. Inset shows plasma appearance 4 h after the lipid load (wild-type on the left and Ces1/Es-x^−/− on the right). *p<0.05 vs. wild-type. (B) Chylomicron clearance. Labeled chylomicrons were isolated from plasma of wild-type and Ces1/Es-x^−/− mice and injected into abdominal veins of mice of both genotypes. Blood samples were collected, plasma prepared and radioactivity measured by scintillation counting. N = 6 mice/group. ***p<0.001 black line vs. blue line, ^###p<0.001 green line vs. red line. (C) In vitro lipolysis of chylomicrons from wild-type, Ces1/Es-x^−/− and ApoE^−/− mice by isolated LpL. N = 3 mice/group. Details about the procedure are given in the main text. *p<0.05 vs. Es-x ^−/−, **p<0.01 vs. Es-x ^−/−; ***p<0.001 vs. ApoE^−/−, ^##p<0.01 vs. ApoE^−/−. (D) Immunobotting showing hepatic LDLr protein expression from fasted and re-fed (6 h) mice.