Stimulation of Wound Revascularization by Adenosine Receptor Activation - Extracellular ATP and Adenosine as Regulators of Endothelial Cell Function - page 100

tissue (Fig. 6.5) [37]. Similarly to A 2A deficient mice, mice lacking the adapter
protein in the pathway of Toll-like receptors MyD88 heal at a markedly slower
rate than wounds in wild-type mice, showing delayed contraction, decreased and
delayed granulation tissue formation, and reduced new blood vessel density. The
A 2A receptor agonist CGS21680 promoted wound closure and angiogenesis in wild

Fig. 6.5 Histological examination of representative sections of untreated and CGS-21680-treated
excisional wounds in wild-type mice and air pouch wall in wild-type and A 2A receptor deficient
mice. ( a ) On day 3 after wounding, mice were killed and the wounds dissected out, embedded
in paraffin, and stained with H&E using standard techniques. Original magnifications 400 1:

Wild-type mouse treated with vehicle 2: Wild-type mouse treated with CGS-21680, arrows indi-
cate blood vessels containing erythrocytes. ( b ) Subcutaneous vesicles were formed on the backs
of wild-type and knockout mice by injecting 3 ml of steril air and were reinflated later with
1.5 ml of steril air two days. After 6 days, the mice were killed and the pouches dissected out.
The dissected pouches were fixed, embedded in paraffin, and stained with H&E using standard
techniques ( 1 and 2 ) or stained immunohistologically with a goat anti-Factor VIII antibody, visu-
alized by immunoperoxidase-mediated conversion of diaminobenzidine, and counterstained with
hematoxylin ( 3 and 4 ). 1: Shown is a representative section from a pouch wall from a female wild-
type mouse (original magnification, × 100). 2: Shown is a representative section from a pouch wall
from a female A 2A receptor knockout mouse (original magnification,

×

×

100). 3: Shown is a repre-
sentative section from a pouch wall from a female wild-type mouse (same block as in 1 ; original
magnification, 400). 4: Shown is a representative section from a pouch wall from a female knock-

out mouse (same block as in 2 ; original magnification

×

× 400). Reprinted from [37] with permission