Figure 3
Arsenic inhibits SEC scavenging of acylated protein.
(A) Mice were injected in the tail vein with 150 mg/kg FITC-labeled succinylated BSA (suc-BSA) or BSA (both green) in 200 μl saline. After 10 min, the mice were euthanized, and livers were excised, fixed in 4% paraformaldehyde, and sectioned for confocal microscopic analysis. Sections were stained with rhodamine-conjugated antibody to PECAM-1 (red) and DRAQ5 (blue). Images are representative of sections from 3 mice in each group. LV, large vessel; S, sinusoid vessel. Scale bar: 10 μm. (B) FITC-labeled acetylated LDL and biotin-labeled succinylated BSA (3 ml; 150 mg/ml saline) were infused over 3 min into the vena cavas of untreated mice and mice exposed to 100 ppb arsenic (As) for 2 wk. Livers were then excised, frozen in liquid N2, and sectioned, and total protein was extracted for assay of retained biotin label by immunoblotting, as described in Methods. Data are mean ± SD band density of biotin-labeled succinylated BSA normalized to β-actin (n = 3). NT, not treated. (C) Isolated SECs, incubated in the absence or presence of 1 mM tempol for 10 min, were left untreated or exposed to 2.5 μM arsenite for 24 h. Biotin-labeled succinylated BSA (20 μg/ml) was then added for 10 min, and after rinsing, total proteins were extracted for Western analysis (n = 3). Data are presented as in B. *P < 0.05, **P < 0.01 versus control; #P < 0.05 versus arsenic.
