Footpads were fixed in Zamboni’s fixative for 2 hours, washed in PBS and then kept in 30% sucrose/PBS overnight at 4°C. The samples were embedded in OCT compound and stored at-80°C. Three longitudinal 20 μm-thick footpad sections from each mouse were prepared.
The following primary antibodies were used: polyclonal rabbit anti-Ang1 (1:2000, Abcam), monoclonal mouse anti-CD31 antibody (1:500, BD Biosciences), polyclonal rabbit anti-S100 (1:400, Abcam) and polyclonal rabbit anti-protein gene product 9.5 (PGP9.5, 1:1000, MILLIPORE). Rabbit or goat IgG was used as a negative control. Sections were counterstained with 4′, 6-Diamidino-2-phenylindole (DAPI) (1:5000, Thermo Scientific).