Chief cells granules

The morphology of the different cell types, except for the chief cells in the rat, has also been found to be normal [1]. Some chief cells in rats after long-term treatment contain eosinophilic granules, an observation which has also been reported to occur after treatment with other inhibitors of gastric acid secretion, including H2-receptor blockers [5]. 

Mast Cells and Basophils. The chief sites of histamine storage are mast cells in the tissues and basophils in blood. These cells synthesize histamine and store it in secretory granules along with a heparin-protein complex. In response to specific antigens, mast cells or basophils are sensitized. Histamine is then secreted from the storage granules. Besides the histamine stores in mast cells and basophils, there is evidence of non-mast cell histamine in some tissues, particularly gastric and intestinal mucosa (60). 

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