EXTRACTION RESISTANCE OF SUDAN STAINED MAST CELLS AFTER PREVIOUS ACID TREATMENT

Abstract

1. Sudan black B alone stains the mast cells very faintly. The granules do not appear very distinct or numerous. 2. The periodic acid Schiff (PAS) technique stains the mast cells; however, the results are variable. When stained, the mast cell granules appear slightly darker than the cytoplasm. 3. When PAS and Sudan black are used together, the mast cell granules gain an avidity for the dye and are stained black. 4. Brief acid treatment prior to immersion in Sudan black results in granules gaining an avidity for the Sudan dye that is extraction resistant. The reaction appears dependent upon modifying the mast cell granules by acid treatment. It appears as though the hydrogen ion changes some physical or chemical property of the granules so that they gain an avidity for the dye. 5. Acetylated Sudan black shows an affinity for the mast cell granules greater than Sudan black alone. This is not increased by previous acid treatment. Acetylated Sudan black also stains the mast cell nucleus.