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Assessment of Vascular Regeneration in the CNS Using the Mouse Retina
Published on: June 24, 2014
The human hyaloid system: cell death and vascular regression
M Zhu1, M C Madigan, D van Driel
1Department of Clinical Ophthalmology, University of Sydney, Sydney, New South Wales 2006, Australia. meidong@eye.usyd.edu.au
Experimental Eye Research
|June 14, 2000
Summary
This study reveals that apoptosis and necrosis are key processes in human fetal hyaloid vascular regression. Apoptosis dominates early regression, while necrosis becomes more prominent in later stages of this vascular development.
Area of Science:
- Ophthalmology
- Developmental Biology
- Cell Biology
Background:
- The regression of the human fetal hyaloid vasculature is a critical developmental process.
- Understanding the cellular mechanisms, specifically cell death pathways, is essential for comprehending this regression.
Purpose of the Study:
- To investigate the roles of apoptosis and necrosis in the regression of the human fetal hyaloid vasculature.
- To characterize the cellular events and cell death modalities involved in vascular regression during human fetal development.
Main Methods:
- Analysis of 67 human fetal hyaloid specimens (10-20 weeks' gestation).
- Immunolabeling with anti-von Willebrand factor and MHC class I antibodies.
- Terminal deoxynucleotidyl transferase-mediated dUTP-biotin DNA nick-end labeling (TUNL) technique.
- Acridine orange/ethidium bromide staining and transmission electron microscopy.
Main Results:
- Vascular regression, including cell loss and thinning, was evident after 13 weeks' gestation.
- Apoptosis and necrosis were observed throughout the hyaloid vasculature.
- TUNL and acridine orange/ethidium bromide staining confirmed DNA fragmentation and condensation, indicative of cell death.
- Hyalocytes may play a role in vascular regression.
Conclusions:
- Both apoptosis and necrosis contribute to human fetal hyaloid vascular regression.
- Apoptosis is more prevalent in early regression, with necrosis becoming more significant in later stages.
- Cell death mechanisms are crucial for the normal developmental regression of the fetal hyaloid vasculature.
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