CTαIKO mice fed a HFD have impaired passage of FAs from the intestinal lumen into enterocytes. Jejunal TG concentrations of female control and CTαIKO mice after fasting (A) or 2 h after refeeding the HFD (B) (n = 5 or 6 per group). Male control and CTαIKO mice were fasted for 4 h on day 3 following initiation of the HFD before receiving an oral bolus of 5 µCi [3H]-labeled triolein in 150 µl of olive oil for 2 h (n = 5 per group). C: Radiolabel in intestine segments 2 h after [3H]-labeled triolein gavage. D: Plasma radiolabel before and 30, 60, 90, and 120 min after a [3H]-labeled triolein gavage. Female control and CTαIKO mice were fasted for 4 h on day 3 following initiation of the HFD before receiving an oral bolus of BODIPY-labeled olive oil. E: Representative H&E-stained proximal intestine sections of control and CTαIKO mice 2 h after oil gavage. F: Fluorescence microscope images of jejunal sections 2 h after BODIPY-labeled oil gavage. G: Representative transmission electron micrographs of jejunal enterocytes 2 h after oil gavage. H: Jejunal mRNA abundance of genes involved in chylomicron and lipid droplet formation (n ≥ 5 per group). I: FAs in fecal samples from female control and CT αIKO mice (n = 5 per group). Values are means ± SEM. * P < 0.05; ** P < 0.01; *** P < 0.001. Cidec, cell death-inducing DFFA-like effector c; Dgat2, diacylglycerol O-acyltransferase 2; Mttp, microsomal TG transfer protein.