Effect of astragalus polysaccharide powder injection on the density of microvessels and mast cells in ovalbulmin-sensitized rat skin

In order to investigate the effects of Astragalus polysaccharide(APS) on microvessels and mast cells,the experiment was based on the model of rat sensitized by subcutaneous injection of ovalbulmin(OVA),adopted CD34 immunochemistry method and toluidine blue staining to investigate the effects of APS on microvessels and mast cells in rat skin.After the stimulation of OVA,the densities of CD34+ microvessels and mast cells were significantly increased from 33.6 and 77.2 cells/mm2 to 67.2 and 180.0 cells/mm2,respectively,and the mast cell degranulation occurred around the microvessels.The APS powder injection significantly downregulated the density increase of CD34+ microvessels and mast cells to 39.7 and 99.7 cells/mm2 induced by OVA in rat skin,and decreased the degranulation of mast cells.It is one mechanism of anti-Inflammatory effect of APS that it downregulates the expression of CD34 in microvascular endothelial cells and the increase and degranulation of mast cells around microvessels,which maybe contribute to the adherence reducing between inflammatory cells and microvascular endothelial cells.