Light and transmission electron microscopy revealed in the elastic car
tilage of the human epiglottis the presence of mast cells. Cytoplasmic
granules of these cells contain characteristic cylindrical bodies, wh
ose texture is different from that found in cytoplasmic granules of ma
st cells from other sites. The presence of mast cells in elastic carti
lage, described for the first time, and the different substructure of
their cytoplasmic granules, is considered as another proof of the hete
rogeneity of that cell type.