Related Experiment Videos
Intercellular gaps in the early development of chick mural endocardium. A TEM study
Insights
Early chick heart development shows endocardial invagination into the ventricular wall. This process involves close interactions between the endocardium and myocardium during trabeculation.
Area of Science:
- Developmental Biology
- Cardiovascular Research
- Histology
Background:
- The early development of the heart, particularly trabeculation, is crucial for cardiac function.
- Understanding the role of the endocardium in heart morphogenesis is essential.
Purpose of the Study:
- To investigate the behavior and morphology of the ventricular mural endocardium during early trabeculation in embryonic chick hearts.
- To analyze the relationship between the endocardium, myocardium, and cardiac jelly during development.
Main Methods:
- Light microscopy and Transmission Electron Microscopy (TEM) were used.
- Serial sectioning of embryonic chick hearts (Hamburger-Hamilton stages 15-21) was performed.
Main Results:
- An invagination of the endocardial layer lining intertrabecular and intermuscular spaces was observed.
- Frequent appositions and contacts between mural endocardium and myocardium were noted.
- The cardiac jelly was consistently an acellular and attenuated matrix.
Conclusions:
- The study elucidates the dynamic invagination of the endocardium during early chick heart trabeculation.
- Observed endocardial-myocardial interactions suggest a role in cardiac development.
- Intercellular gaps in the endocardium were not directly linked to intertrabecular space endothelialization.
Abstract:
Embryonic chick hearts stages 15 to 21 according to the Hamburger-Hamilton series (1951) were subjected to TEM and light-microscopical examination to investigate ventricular mural endocardium during early trabeculation. Serial sectioning of consecutively-aged embryos indicated an invagination of the endocardial layer which lines the intertrabecular and intermuscular spaces. During the proceeding development, frequently occurring approaches and contacts between mural endocardium and myocardium could be observed. At all stages examined, the cardiac jelly appeared as an acellular, at particular sites very attenuated matrix. The intercellular gaps of the endocardium could not be correlated to the invagination and the endothelialization of the intertrabecular spaces.