Optimization of the Method for the Identification of Mast Cells Using Cresyl Violet

Mast cells are an important component of connective tissue and can be selectively visualized with basic aniline dyes. One of them is cresyl violet, which stands out among others due to its capacity for fluorescence. The aim of this study is to optimize the histochemical method of cresyl violet staining for the selective detection of mast cells in rat myocardium. In this work, various staining protocols are presented for transmitted light microscopy of the visible range and for confocal microscopy. It is shown that the highest degree of staining selectivity can be achieved by differentiating the staining with hydrochloric acid. High color contrast, achieved due to pronounced metachromasia, between mast cells and surrounding tissue elements can be achieved using an aqueous mounting medium. Fluorescent cresyl violet staining in combination with confocal microscopy allows a clearer visualization of mast cell granules and the study of their structure.