Ezetimibe Promotes Brush Border Membrane-to-Lumen Cholesterol Efflux in the Small Intestine
Fig 2
Ezetimibe increases brush border membrane-to-lumen cholesterol efflux.
A, An example of jejunal cannulation for the luminal perfusion assay (129+Ter/SvJ mouse). B, An illustrated protocol for the luminal perfusion assay. Assay time course is indicated from left to right. Arrow heads show time points when reagents were given to mice. C, Upper; Plots for 3H-decay per minute (DPM) counts in the perfusate (right, gray circles) and the perfused intestinal segment (left, open circles). Lower; 3H-DPM in the perfusate was divided by that in the intestinal segment perfused to obtain a ratio (%), which was then converted to a common logarithm, and compared using Dunnett’s test. Circles show vehicle controls or ezetimibe treatment (1–50 μg). Triangles, methyl-β-cyclodextrin (MβCD), a cholesterol absorbent; 20 mg/ml in the perfusion buffer. Each plot shows an individual assay result. D, Intestinal 3H-DPM abundance did not change apparently during luminal perfusion assay. Intestinal segments were obtained 3 h after the labeling with 3H-cholesterol (open circles) or after luminal perfusion assay (gray circles) for DPM count (separate experiments from Fig 2C). Bars show median DPM of each group. Each plot shows an individual assay result. The data for the perfused columns were obtained from the data shown in C, which were divided with the respective intestinal lengths perfused (cm). E, Elution pattern of 3H-cholesterol from the intestinal lumen with 0–50 μg/mouse ezetimibe in luminal perfusion assays of C. The inset shows fractional perfusate/intestine 3H-DPM ratios (fractional efflux efficiency).