Fig. 4.

Immunohistochemistry for P-gp protein in the yolk sac from LPS treated mice (n = 8/group). A: negative control of technique by primary antibody omission. B and C: P-gp immunolabeling in the yolk sac from mice at GD15.5 after 4 h of treatment with vehicle (B) and with LPS (C). In the insert in B, it is possible to observe the endodermic epithelium and an area of the mesothelium intensely stained, while the endothelium of a blood vessel displays no labeling. D, E and F: P-gp immunolabeling in the yolk sac from mice at GD18.5, after 24 h of treatment with vehicle (D), and after 4 h (E) and 24 h (F) of treatment with LPS. Arrowheads: endodermic epithelium; thin arrows: mesothelium; asterisk: mesodermal blood vessels. G, H, I and J: Semiquantitative evaluation of area and intensity of P-gp immunolabeling. No significant differences were observed. *p < 0,05, Mann Whitney test.