Fig. 4.

Plasma decay, biliary cholesterol secretion, and TICE of radiolabeled cholesterol from HDL in Abca1^−/−×Sr-b1^−/− mice. After injection of [³H]CO-labeled HDL into Abca1^−/−×Sr-b1^−/− mice and their WT littermates (n = 4), plasma samples were obtained at indicated time points and plasma decay was determined (A). At 1 h after injection, bile cannulations and intestine perfusions were performed to determine biliary cholesterol secretion (B) and TICE (C, D). Both total cholesterol and ³H activity were measured in bile, plasma, perfused intestine, and perfusate and the specific radioactivities are expressed as dpm/nmol cholesterol. Values are means ± SD. * indicates a significant difference between Abca^−/− and WT littermates (P < 0.05).