Figure 4.

NPC1L1-mediated sphingomyelin uptake in vitro. (A) Protein expressions of NPC1L1-HA and α-tubulin (as a loading control) were examined in NPC1L1-overexpressing Caco-2 cells (NPC1L1 cells) and control Caco-2 cells (control cells) by Western blot analysis. (B) Uptake of sphingomyelin (SM) by NPC1L1 cells and control cells was examined after incubation for 3 h with [³H] SM-containing medium in the absence (−) or presence (+) of 40 μM ezetimibe (Eze). Bar graphs represent the mean ± S.D. Each dot on the bar graphs represents a single well of a cell culture plate from three independent experiments (n = 9). ** p < 0.01, significant difference by Dunnett’s test between control cells and NPC1L1 cells in the absence of ezetimibe. †† p < 0.01, significant difference by Dunnett’s test comparing two groups [Eze (−) and Eze (+)]. N.S., no significant difference between groups.