Endovascular irradiation impairs vascular functional responses in noninjured pig coronary arteries
| Autor: | John Todd, Keith A. Robinson, Jinsheng Li, Jianhua Cui, Nicolas Chronos, Bunken Ebato, Hector De Leon |
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| Rok vydání: | 2002 |
| Předmět: |
Male
medicine.medical_specialty Time Factors Endothelium Prostaglandin Substance P Muscle Smooth Vascular Nitric oxide chemistry.chemical_compound Isometric Contraction Internal medicine medicine Animals Endothelial dysfunction Superoxide business.industry Angioplasty Anatomy medicine.disease Coronary Vessels Beta Particles Femoral Artery Vasomotor System Coronary arteries Disease Models Animal Endocrinology medicine.anatomical_structure chemistry Swine Miniature Molecular Medicine Female Surgery Endothelium Vascular Sodium nitroprusside Cardiology and Cardiovascular Medicine business medicine.drug |
| Zdroj: | Cardiovascular Radiation Medicine. 3:152-162 |
| ISSN: | 1522-1865 |
| DOI: | 10.1016/s1522-1865(03)00096-9 |
| Popis: | Purpose: To assess the effects of endovascular irradiation on vascular structure and function in pig coronary arteries in the absence of vascular injury. Methods and Materials: Vasomotor responses to contractions of KCl and prostaglandin F2α (PGF 2α ), relaxations to endothelium-dependent (substance P, A23187) and -independent (sodium nitroprusside, SNP) agents; endothelial morphology and superoxide anion (O 2 ·− ) production were investigated in control (naive), sham and irradiated (20 Gy, 32 P) arteries 1 month after irradiation. Results: Contractions to KCl and PGF 2α in the presence of l-NAME were significantly decreased, relaxations to substance P and A23187 were abolished and SNP-induced relaxation was potentiated in irradiated arteries compared to naive and sham-treated vessels. Scanning electron microscopy (SEM) revealed enlarged endothelial cells (ECs) exhibiting surface microvilli. O 2 ·− production was significantly increased in irradiated vessels (437.0±37.3 vs. 126.0±11.6 RLU/s/mg tissue, P Conclusions: One month after brachytherapy, normal pig coronary arteries showed abnormal vascular reactivity, altered endothelial morphology and increased production of O 2 ·− . Lack of relaxation to substance P and A23187 reflects ionizing radiation-mediated damage to ECs, whereas potentiation of relaxation to SNP suggests additional deleterious effects on medial smooth muscle cells (SMCs). Increased O 2 ·− production might have contributed to endothelial dysfunction by scavenging nitric oxide (NO). |
| Databáze: | OpenAIRE |
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