Ontogeny of ECL cells in the rat.

ECL cells produce histamine and chromogranin A, and are restricted to the oxyntic mucosa of the stomach. ECL cell ontogeny has been studied in some detail in the rat. Using histidine decarboxylase immunostaining, the first ECL cells can be demonstrated at embryonic day 17. Immunoreactive histamine and chromogranin A appear one day later. At embryonic day 20, the vesicular monoamine transporter type 2 is also present in the ECL cells. Neonatally the ECL cell proliferation is slow; however, one to three weeks postnatally there is a rapid growth of ECL cells to populate the basal half of the glands. Gastrin is known to be an important stimulator of ECL cell activity and growth in the adult rat. As revealed in recent mouse gene knock out models gastrin does not seem to play a role in the early ECL cell differentiation and development.