A study of the enteroendocrine cells of the gastrointestinal tract of the chick embryo

The enteroendocrine cells of the gastrointestinal tract of the chick embryo have been studied. Light micro- scope techniques were used to determine the distribution of argyrophile cells in the proventriculus, gizzard, duodenum, ileum and large intestine. Argyrophile cells were present as early as the day 13 incubation stage and were distributed throughout the intestinal tract by day 16. Using Electron microscope techniques, 8 enteroendocrine cell types were described, based on size, shape, and electron density of granules in the basal and peripheral cytoplasm. The cell types were designated EC,K,V, 5,D,D₁,A-like, and G. This study has shown that the gut possesses a diffuse yet extensive system of cells which can respond to various stimuli from the digestive tract.