Related Experiment Videos
Intestinal endocrine cells of chicks around the time of hatching
Insights
Electron microscopy identified endocrine cells in chick embryonic intestines, similar to those in mammals. Their distribution suggests conserved functions in avian and mammalian gastrointestinal systems.
Area of Science:
- Comparative anatomy
- Avian embryology
- Gastrointestinal histology
Background:
- Endocrine cells in the mammalian gut play crucial roles in regulating digestion and metabolism.
- Understanding the homologous cells in avian species provides insights into evolutionary conservation of gut functions.
Purpose of the Study:
- To investigate the presence and distribution of endocrine cells in the developing chick embryo gastrointestinal tract.
- To compare the characteristics of these cells with known mammalian enteroendocrine cell types.
Main Methods:
- Electron microscopy was used to examine tissue samples from Black Australorp chick embryos at different developmental stages (16-day and 18-day embryos) and newly hatched chicks.
- Cellular structures, specifically secretory granules, were analyzed for similarities to mammalian endocrine cell markers.
Main Results:
- Cells with secretory granules resembling mammalian EC, S, A-like, EG, and D cells were identified in the chick duodenum, ileum, large intestine, and caeca.
- The observed distribution and frequency of these putative endocrine cells in the chick gut closely mirrored patterns found in mammalian species.
Conclusions:
- The study provides evidence for the presence of homologous enteroendocrine cells in avian and mammalian gastrointestinal tracts.
- These findings suggest a conserved evolutionary origin and potentially similar functional roles for these cells in regulating gut physiology across different vertebrate classes.
Abstract:
The duodenum of 16-day Black Australorp chick embryos, and the duodenum, ileum, large intestine and caeca of 18-day embryos and of chicks within 30 h of hatching, have been studied by electron microscopy. Cells were found with secretory granules resembling those in mammalian EC, S, A-like, EG and D cells (terminology of Solcia et al., 1973), and were on this basis tentatively identified accordingly. The distribution and frequency of the chick cells in different parts of the tract correspond well to the situation in mammals.