Fig. 5.

PVAT and BAT are resistant to inflammation after 13 wk of HFD. SAT (A and B), VAT (C and D), BAT (E and F), and PVAT (G and H) from the aortic arch was harvested from lean and obese mice (n = 3 per group). Samples were fixed in 4% formalin, sectioned, and stained with a rat anti-mouse F4/80 primary antibody (ABd Serotec). Staining was visualized with a horseradish-peroxidase-linked rabbit anti-rat secondary antibody. Abundant macrophages were seen predominantly in VAT, but also SAT, forming crown-like structures (arrowheads). No macrophages were seen in BAT or PVAT (magnification: ×25).