Fig. 1.
Age-dependent stimulation of VLDL secretion and liver MTP activity in Pcyt2+/−mice. A: Fasting plasma TAG was measured in 8, 32, and 42 week-old Pcyt2+/− mice and littermate controls. Plasma LPL was inhibited with P407 injection, and VLDL-TAG was determined in 0–4 h intervals. At 8 weeks of age, VLDL-TAG secretion was similar in Pcyt2+/− mice and control littermates. A modest but significant increase in VLDL secretion was present in 32-week-old Pcyt2+/− mice; and 42-week-old Pcyt2+/− mice showed significantly elevated VLDL secretion compared to littermates. The level of activity (B) and expression (C) of the liver MTP in 8, 32, and 42 week-old mice. MTP activity was expressed as fluorescence (F) U.min−1.μg of protein−1 for n = 5 mice in each group. Statistical significance (* and **) at each point was determined by Student's t-test at P < 0.05.