Fig. 5.
Two examples of mast cell granules in pre-synaptic elements (as defined by the clustering of synaptic vesicles, arrowheads). (A) The inclusion is an expanded remnant (G) similar to the particulate granules in the neighboring mast cell (Gmc). Also note a granule remnant (g) external to either cell and surrounded by filopodia (arrows). In B a pre-synaptic terminal contains a granule (*) with a well-defined membrane and vesicular interior (*). An externalized granule (g) is present, surrounded by mast cell filopodia (arrows). Ax, axon; As, astrocyte; d, dendrite; MC, mast cell; m, mitochondrion.