Figure 3  .

Effect of chronic stress on mast cells in +/+ rats. (A) A non-activated mast cell (MC) in the mucosa of a sham stressed +/+ rat showing numerous homogeneous electron dense granules. (B) A mast cell (MC) with piecemeal-type degranulation. The mast cell is in close apposition to an emptied nerve terminal (N) in the mucosa of a stressed +/+ rat, and shows loss of intragranular density without fusion of intergranular membranes, retained oval granules in the cytoplasm, and absence of extruded granules contents or granule membranes, indicative of piecemeal-type degranulation. (C) A mast cell (MC) in the mucosa of a stressed +/+ rat showing enlarged granules with solubilisation of intragranular contents, fusion of intergranular membranes (arrows), and absence of extruded material, indicative of a mixed anaphylactic-piecemeal degranulation pattern. Magnification: A-C, ×3000.