Figure 5From: Complementary effects of extracellular nucleotides and platelet-derived extracts on angiogenesis of vasa vasorum endothelial cells in vitro and subcutaneous Matrigel plugs in vivoThe effects of platelet extracts and adenine nucleotides on Matrigel plug vascularization. Matrigel (200 μl per plug) was mixed with platelet extracts (29 μg/ml and 58 μg/ml), ATP (1 mM), mixture of MeSATP, ATPγS, MeSADP, and ADPβS (0.1 mM, 0.5 mM or 1 mM of each), combination of nucleotides and platelet extracts (concentrations as indicated), or vechicle (10 mM HCl in PBS) and injected subcutaneously into ICR mice (n = 4-5 for each group). After 7 days, mice were sacrificed, Matrigel plugs were excised, and 5-7 μm-thick sections were prepared from formalin fixed plugs/paraffin-embedded plugs. H&E staining was performed for identification of plug cellularity and tube formation. Representative images show (a): control plugs, ×40; (b): plugs containing 58 μg/ml platelet extract (×40; insert shows magnified view of an capillary containing red blood cells); (c-d): plugs containing 0.5 mM purine nucleotides (panel c = ×40, panel d = x10 magnification; arrows on the panel c indicate areas of increased plug cellularity); platelet extracts (58 μg/ml), mixture of MeSATP, ATPγS, MeSADP, and ADPβS (0.1 mM, 0.5 mM or 1 mM of each), (e-f): plugs containing platelet extracts (58 μg/ml) and mixture of nucleotides (0.5 mM of each); panel e: plug with increased amount of functional capillaries (enlarged in the insert); panel f: blood cell infiltrates around new formed capillaries (enlarged in the insert); (g-j): Identification of PECAM-positive cells in control plugs (g) and plugs containing 58 μg/ml platelet extract (h), mixture of nucleotides (0.5 mM of each), and combination of 58 μg/ml platelet extract and mixture of nucleotides (0.5 mM of each, j). PECAM-positive cells are shown enlarged in the inserts.Back to article page