Related Experiment Video
Updated: Aug 30, 2026
Placing Growth Factor-Coated Beads on Early Stage Chicken Embryos
Published on: September 30, 2007
Growth-promoting effects of endothelin-1 and endothelin-3 on chick embryos
Insights
Endothelin-1 and endothelin-3 promote chick embryo development, enhancing brain and body size. Optimal effects were observed with treatment around the 5th day of incubation, suggesting growth factor-like roles.
Area of Science:
- Developmental Biology
- Neuroscience
- Endocrinology
Background:
- Endothelin peptides (ET-1, ET-3) are known regulators of cardiovascular function.
- Their role in embryonic development, particularly brain maturation, requires further investigation.
Purpose of the Study:
- To investigate the effects of endothelin-1 and endothelin-3 on chick embryo development.
- To determine the optimal timing and dosage for endothelin treatment during early embryogenesis.
Main Methods:
- Chick embryos were treated with varying doses of ET-1 or ET-3 at different developmental stages (days 1-5, day 5).
- Embryo size, brain morphology (telencephalic and optic lobes, diencephalon), and tissue histology were analyzed.
Main Results:
- ET-1 and ET-3 treatment increased overall embryo size (head, trunk, beak, wings) by 5-14%.
- Embryonic brain regions, including telencephalic and optic lobes, showed increased dimensions (4-14%).
- Histological analysis revealed more cellular and organized brain tissue in ET-treated embryos, indicating maturation rather than non-specific growth.
Conclusions:
- Endothelin peptides exhibit growth factor-like effects on chick embryo development.
- Treatment around the 5th day of incubation appears most effective for promoting early brain development.
- No significant vascular abnormalities or malformations were observed, suggesting a safe developmental influence.
Abstract:
Chick embryos were treated with single or multiple doses of 0-250 pmol of endothelin-1 (ET-1) or endothelin-3 (ET-3) and their effects on development were examined in embryos ranging from 7 to 14 days in age. The overall sizes of the head, trunk, beak or wings were increased (5-14%) in ET-treated embryos. Additionally, the lengths or widths of the telencephalic or optic lobes and the diencephalon in the embryonic brains were also increased (4-14%). These effects were observed when the embryos were treated with ET for three consecutive days beginning on day 2 of incubation or from day 1-5. Similar results were obtained by a single injection given on the 5th day of incubation, but not on day 1 or 3. Morphological studies suggested that ET-1 and ET-3 promoted maturation rather than non-specific growth in size. Histological studies revealed that ET-treated brain tissues were more cellular and organized in appearance than control brains. There was no increased incidence of vascular abnormalities or structural malformations subsequent to ET-treatment. These results suggest that ET has growth factor-like effects and that treatment on and around the 5th day of incubation seemed to be most effective for the early phase in brain development in chick embryos.
