RESUMO
Objective To investigate the role of mast cell activation products in promoting angiogenesis. Methods SD rat peritoneal mast cells (RPMC) were isolated and activated by calcium ionophore. The activation products were extracted and the activity of chymase was detected. Thirty BALB/c mice were randomly divided into a control group, an activation product group, and an inhibitor group (10 mice in each group), and the angiogenisis of mast cell activation products was studied by matrigel plug assay. In the matrigel plug, the hemoglobin (Hb) concentration was determined by hemiglobincyanide (HiCN) method, the distribution of blood vessels was observed by HE staining, and the microvessel density (MVD) was detected by CD34 immunohistochemical staining. Results The activity of chymase was detected in the activation products of isolated RPMCs. The results of mice matrigel plug assay showed that the Hb level in matrigel plug of the activation product group was about 7 times higher than that of the control group, while the Hb level of the inhibitor group was 80.8% lower than that of the activation product group. HE staining showed new blood vessels in the matrigel plug of the activation product group, and some vascular lumens were observed. The results of MVD showed that the MVD in matrigel plug of the activation product group was about 5 times than that of the control group, while MVD of the inhibitor group was 66.2% lower than that of the activation product group. Conclusion Chymase, a product of mast cell activation, is the main mediator to promote angiogenesis in mouse matrigel plugs.