Figure 1. Cyp7a1-tg mice have increased cholesterol synthesis and decreased fatty acid synthesis in the liver.

A. Hepatic cholesterol and fatty acid synthesis rates were measured as described in Materials and Methods. The activities of ³H and ¹⁴C were determined in a scintillation counter. The cholesterol and fatty acid synthesis rates were expressed as ¹⁴C radioactivity derived from ¹⁴C-acetate (adjusted by internal recovery standard ³H-cholesterol radioactivity) and incorporated into cholesterol or fatty acids per minute per gram liver tissue. B. Wild type and Cyp7a1-tg mice were ip. injected with a single dose of glucose (8 g/kg) containing 5 µCi [1-¹⁴C] glucose, and fecal ¹⁴C sterol amount was estimated as described in Materials and Methods. The fecal acidic sterols (bile acids) and neutral sterols (cholesterol) derived from ¹⁴C-glucose were estimated by measuring the radioactivity of ¹⁴C incorporated, adjusted by internal standard ³H-cholesterol radioactivity, and expressed as percentage of total administrated ¹⁴C activity. Results are expressed as mean ± SE; “*” indicates p < 0.05 vs. WT. “**” indicates p < 0.05 vs. ¹⁴C incorporation into cholesterol in WT mice, n = 4-5.