Secretory granules

Mast cells are connective tissue cells that can be readily identified by their coarse secretory granules.  These granules have a reddish color with H & E staining and a purplish-blue color with toluidine blue.  Mast cell granules contain histamine and heparin, which are released following exposure to allergens.  Numerous capillaries are also present.  Testis  1000x

Mast cells are connective tissue cells that can be readily identified by their coarse secretory granules.  These granules have a reddish color with H & E staining and a purplish-blue color with toluidine blue.  Mast cell granules contain histamine and heparin, which are released following exposure to allergens.  Numerous capillaries are also present.  Testis  1000x