HISTOCHEMICAL AND CYTOCHEMICAL STUDIES ON NEWT LUNG MAST-CELLS

Mast cells which show metachromasia with toluidine blue were observed in newt (Cynops pyrrhogaster) lung connective tissue. The mast cells s howed strange granules in their cytoplasm. In this study, we examined the characteristics of the mast cells by using histochemical and cytoc hemical methods. The mast cells were positive for PAS reaction and Alc ian blue (pH 1.0). Electron microscopy showed that the mast cells stre tched their cytoplasm into the collagen layer. The cytoplasm was fille d with various types of granules, some homogeneous throughout, others heterogeneous, and were classified as follows: high and low electron d ensity amorphous structure, straight lamella structure, and rough part icle structure. These granules were irregular in size. They were stain ed by alkaline bismuth and dialyzed iron. The rough particle structure granules in particular showed stronger staining than others. In order to determine which sulfated polysaccharide was contained in the granu les, we performed enzyme treatment using two enzymes chondroitinase AB C (pH 8.0) and heparinase. Our results indicated that the granules con tained heparin.