Dopamine and Mesenchymal Stem Cells Figure 3. Dopamine (DA) D2 receptor antagonist treatment stimulate incorporation of MSCs into neovessels of wound bed and subsequent angiogenesis in wound bed. (A) Effect of eticlopride treatment on incorporation of transplanted MSCs into newly formed blood vessels in wound bed. MSCs were labeled with CM-Dil and injected into the tail vein of both control and eticlopride treated back skin-injured mice. At day 6, the skin from the wound area was collected and sectioned with cryomicrotome. Frozen sections were immunostained with anti-CD31 antibody and FITC-conjugated secondary antibody and analyzed to determine the extent of incorporation of transplanted MSCs into blood vessels. Here co- localization study showed that exogenously transplanted MSCs, labeled with fluorescent dye CM-Dil (red in colour), had integrated into the newly formed blood vessels (green in colour) in wound site in much greater number following DA D2 receptor antagonist treatment than vehicle treated controls. Original magnifications, 6200. (B) Effect of MSC transplantation on formation of new blood vessels in wound bed. Immunohistochemical PLoS ONE | www.plosone.org 5 February 2012 | Volume 7 | Issue 2 | e31682