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Updated: Jul 12, 2026
09:03
Monitoring Functionality and Morphology of Vasculature Recruited by Factors Secreted by Fast-growing Tumor-generating Cells
Published on: November 23, 2014
Opioid growth factor modulates angiogenesis
J Blebea1, J E Mazo, T K Kihara
1Department of Surgery and the Department of Neuroscience and Anatomy, The Pennsylvania State University College of Medicine, Hershey, PA, USA.
Journal of Vascular Surgery
|August 5, 2000
Summary
Endogenous opioids, specifically opioid growth factor (OGF), inhibit angiogenesis in vivo. Blocking OGF with naltrexone promotes blood vessel growth, suggesting a therapeutic target for vascular diseases.
Area of Science:
- Molecular Biology
- Vascular Biology
- Endocrinology
Background:
- Induced angiogenesis is a therapeutic strategy for occlusive arterial atherosclerotic disease.
- The role of endogenous opioids in modulating angiogenesis remains largely unexplored.
Purpose of the Study:
- To investigate the potential role of endogenous opioids in regulating angiogenesis.
- To determine if opioid growth factor (OGF) influences blood vessel formation in vivo.
Main Methods:
- Utilized the chick chorioallantoic membrane (CAM) as an in vivo model for angiogenesis.
- Applied OGF, opioid receptor antagonists (naloxone, naltrexone), retinoic acid, and vascular endothelial growth factor (VEGF) to CAMs.
- Quantified blood vessel number and length using digital imaging and performed immunocytochemistry for OGF and its receptor (OGFr).
Main Results:
- Opioid growth factor significantly inhibited angiogenesis, reducing blood vessel number and length by 35% and 20%, respectively.
- Naltrexone, an opioid antagonist, significantly increased blood vessel number and length by 51% and 24%, indicating receptor-mediated effects.
- OGF and OGFr were detected in endothelial and mesenchymal cells of the CAM vasculature.
Conclusions:
- Endogenous opioids, particularly OGF, play a significant role in modulating in vivo angiogenesis.
- OGF acts as a tonically active peptide regulating angiogenesis through receptor-mediated mechanisms.
- These findings highlight a novel pathway for therapeutic intervention in vascular diseases.
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