Intramural Hemorrhage and Endothelial Changes in Atherosclerotic Coronary Artery After Repetitive Episodes of Spasm in X-ray-Irradiated Hypercholesterolemic Pigs

• Published in: Circulation research 1989-08, Vol.65 (2), p.272-282
• Main Authors: Nagasawa, Kazushige, Tomoike, Hitonobu, Hayashi, Yasuo, Yamada, Akira, Yamamoto, Torao, Nakamura, Motoomi
• Format: Article
• Language: English
• Subjects: 560152 - Radiation Effects on Animals- Animals; AMINES; Angiography; ANIMAL TISSUES; ANIMALS; AROMATICS; ARTERIES; ARTERIOSCLEROSIS; AUTONOMIC NERVOUS SYSTEM AGENTS; AZAARENES; AZOLES; Biological and medical sciences; BIOLOGICAL EFFECTS; BIOLOGICAL RADIATION EFFECTS; BLOOD VESSELS; BODY; Cardiology. Vascular system; CARDIOVASCULAR DISEASES; CARDIOVASCULAR SYSTEM; CHOLESTEROL; CORONARIES; Coronary Angiography; Coronary Artery Disease - complications; Coronary Artery Disease - pathology; Coronary Artery Disease - physiopathology; Coronary heart disease; Coronary Vasospasm - complications; Coronary Vessels - radiation effects; DISEASES; DOMESTIC ANIMALS; DRUGS; ELECTROMAGNETIC RADIATION; ELECTRON MICROSCOPY; ENDOTHELIUM; Endothelium, Vascular - pathology; Heart; Hemodynamics; HEMORRHAGE; Hemorrhage - etiology; HETEROCYCLIC COMPOUNDS; HYDROXY COMPOUNDS; Hypercholesterolemia - complications; INDOLES; IONIZING RADIATIONS; Male; MAMMALS; Medical sciences; MICROSCOPY; Microscopy, Electron; MINIATURE SWINE; MYOCARDIAL INFARCTION; NEUROREGULATORS; ORGANIC COMPOUNDS; ORGANIC NITROGEN COMPOUNDS; ORGANS; PATHOGENESIS; PATHOLOGICAL CHANGES; PERFUSED ORGANS; PYRROLES; RADIATION EFFECTS; RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT; RADIATIONS; RADIOPROTECTIVE SUBSTANCES; SEROTONIN; STEROIDS; STEROLS; SWINE; Swine, Miniature; SYMPATHOMIMETICS; SYMPTOMS; TISSUES; TRYPTAMINES; VASCULAR DISEASES; VERTEBRATES; X RADIATION
• ISSN: 0009-7330; 1524-4571
• DOI: 10.1161/01.res.65.2.272

To assess whether coronary spasm affects the progression of atherosclerosis and results in evolution of myocardial infarction, the role of coronary spasm on the fine structure of conduit coronary arteries was studied morphologically. Göttingen miniature pigs were fed a semisynthetic diet containing 2% cholesterol and 1.1% sodium cholate. One month after being on this diet, the pigs were anesthetized and the endothelium of a branch of the left coronary artery was denuded using a balloon catheter. X-ray irradiation in a dose of 1,500 rad was given twice selectively to the area denuded, after 4 and 5 months of cholesterol feeding. Five months after endothelial denudation, transient (group A) and repetitive episodes (group B) of coronary spasm were provoked by single and periodic (five times every 5 minutes) intracoronary injections of serotonin (10 μg/kg/injection), respectively. The extent of spasm by serotonin at the previously denuded site was 84±4% (n=4) and 90±5% (n=6) narrowing in groups A and B (p=NS between groups), respectively. Forty minutes after the final administration of serotonin, the left coronary artery was relaxed by nitroglycerin, and the heart was isolated and perfuse-fixed under physiological pressure. Intramural hemorrhage was noted at the spastic site in six pigs of group B but not in group A. The average percent luminal narrowing, on cross sections at the spastic site in group B, was significantly greater than in group A (56±7% vs. 23±5%,p